Mac air virus

Hi,
my Mac has a virus and I have pop up ads everywhere amd is running slower. I would like to know how i can restore my computer completely? LIke back to factory settings?

There is no need to download anything to solve this problem, nor do you need to reset the computer.
You may have installed one or more of the common types of ad-injection malware. Follow the instructions on this Apple Support page to remove it. It's been reported that some variants of the "VSearch" malware block access to the page. If that happens, start in safe mode by holding down the shift key at the startup chime, then try again.
Back up all data before making any changes.
One of the steps in the article is to remove malicious Safari extensions. Do the equivalent in the Chrome and Firefox browsers, if you use either of those. If Safari crashes on launch, skip that step and come back to it after you've done everything else.
If you don't find any of the files or extensions listed, or if removing them doesn't stop the ad injection, ask for further instructions.
Make sure you don't repeat the mistake that led you to install the malware. It may have come from an Internet cesspit such as "Softonic" or "CNET Download." Never visit either of those sites again. You might also have downloaded it from an ad in a page on some other site. The ad would probably have included a large green button labeled "Download" or "Download Now" in white letters. The button is designed to confuse people who intend to download something else on the same page. If you ever download a file that isn't obviously what you expected, delete it immediately.
Malware is also found on websites that traffic in pirated content such as video. If you, or anyone else who uses the computer, visit such sites and follow prompts to install software, you can expect more of the same, and worse, to follow. Never install any software that you downloaded from a bittorrent, or that was downloaded by someone else from an unknown source.
In the Security & Privacy pane of System Preferences, select the General tab. The radio button marked Anywhere should not be selected. If it is, click the lock icon to unlock the settings, then select one of the other buttons. After that, don't ignore a warning that you are about to run or install an application from an unknown developer.
Still in System Preferences, open the App Store or Software Update pane and check the box marked
Install system data files and security updates (OS X 10.10 or later)
or
Download updates automatically (OS X 10.9 or earlier)
if it's not already checked.

Similar Messages

Pop ups and ads everywhere on mac air- virus?

Hi,
It's been about six months now that the problem has started. Everytime I click on something when browsing the internet another tab will open that usually is a link to mackeeper, random pics of naked ladies, dating sites with half naked women on them etc. It's really embarrassing and frustrating to have to continuously close these pop ups. The problem is worse when using google chrome and not so bad when using firefox. The mac has also become super slow- sites take forever to load and even typing is an issue because it lags a lot, in fact EVERYTHING lags. I'm not tech savy so would like some easy to follow help!!!!

There is no need to download anything to solve this problem. You may have installed a variant of the "VSearch" ad-injection malware.
Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:
/Library/LaunchDaemons
In the Finder, select
          Go ▹ Go to Folder...
from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.
A folder named "LaunchDaemons" may open. Look inside it for a file with a name of the form
          com.something.daemon.plist
Here something is a variable word, which can be different in each case. It could be "cloud," "dot," "highway," "submarine," "trusteddownloads," or pretty much anything else.
There may also be a file named
           com.something.helper.plist
in the same folder.
If you find files with names that fit the above description, post what you have for "something."

Do I have a virus on my Mac Air because I keep getting ads for MacBooster and MacKeeper?

Do I have a virus on my Mac Air because I keep getting ads for MacBooster and MacKeeper?

You may have installed the "VSearch" trojan. Remove it as follows.
Malware is always changing to get around the defenses against it. These instructions are valid as of now, as far as I know. They won't necessarily be valid in the future. Anyone finding this comment a few days or more after it was posted should look for more recent discussions or start a new one.
Back up all data before proceeding.
Step 1
From the Safari menu bar, select
          Safari ▹ Preferences... ▹ Extensions
Uninstall any extensions you don't know you need, including any that have the word "Spigot," "Trovi," or "Conduit" in the description. If in doubt, uninstall all extensions. Do the equivalent for the Firefox and Chrome browsers, if you use either of those.
Reset the home page and default search engine in all the browsers, if it was changed.
Step 2
Triple-click anywhere in the line below on this page to select it:
/Library/LaunchAgents/com.vsearch.agent.plist
Right-click or control-click the line and select
          Services ▹ Reveal in Finder (or just Reveal)
from the contextual menu.* A folder should open with an item named "com.vsearch.agent.plist" selected. Drag the selected item to the Trash. You may be prompted for your administrator login password.
Repeat with each of these lines:
/Library/LaunchDaemons/com.vsearch.daemon.plist
/Library/LaunchDaemons/com.vsearch.helper.plist
Restart the computer and empty the Trash. Then delete the following items in the same way:
/Library/Application Support/VSearch
/System/Library/Frameworks/VSearch.framework
~/Library/Internet Plug-Ins/ConduitNPAPIPlugin.plugin
Some of these items may be absent, in which case you'll get a message that the file can't be found. Skip that item and go on to the next one.
The problem may have started when you downloaded and ran an application called "MPlayerX." That's the name of a legitimate free movie player, but the name is also used fraudulently to distribute VSearch. If there is an item with that name in the Applications folder, delete it, and if you wish, replace it with the genuine article from mplayerx.org.
This trojan is often found on illegal websites that traffic in pirated content such as movies. If you, or anyone else who uses the computer, visit such sites and follow prompts to install software, you can expect more of the same, and worse, to follow.
You may be wondering why you didn't get a warning from Gatekeeper about installing software from an unknown developer, as you should have. The reason is that the Internet criminal behind VSearch has a codesigning certificate issued by Apple, which causes Gatekeeper to give the installer a pass. Apple could revoke the certificate, but as of this writing has not done so, even though it's aware of the problem. This failure of oversight has compromised both Gatekeeper and the Developer ID program. You can't rely on Gatekeeper alone to protect you from harmful software.
*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combination command-C. In the Finder, select
          Go ▹ Go to Folder...
from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.

I bought my mac air in March would it have come with virus protection

Would my mac air come with virus protection when I bought it or do I have to buy separately?

Unless you're running Windows on the computer, all of the malware-protection software you need for it is built into Mac OS X.
(106713)

Virus on my mac air please help.

Virus on my mac air please help every time i click something on a safe website or any even apple website I get redirected to stupid websites that are always random and different each time also when I'm on youtube/apple websites etc. my computer replaces letters and numbers with blue words or numbers that redirect me please help. (I'm in a different country at school so i cannot see apple store for help)

1. This procedure is a diagnostic test. It changes nothing, for better or worse, and therefore will not, in itself, solve the problem. But with the aid of the test results, the solution may take a few minutes, instead of hours or days.
Don't be put off by the complexity of these instructions. The process is much less complicated than the description. You do harder tasks with the computer all the time.
2. If you don't already have a current backup, back up all data before doing anything else. The backup is necessary on general principle, not because of anything in the test procedure. Backup is always a must, and when you're having any kind of trouble with the computer, you may be at higher than usual risk of losing data, whether you follow these instructions or not.
There are ways to back up a computer that isn't fully functional. Ask if you need guidance.
3. Below are instructions to run a UNIX shell script, a type of program. As I wrote above, it changes nothing. It doesn't send or receive any data on the network. All it does is to generate a human-readable report on the state of the computer. That report goes nowhere unless you choose to share it. If you prefer, you can act on it yourself without disclosing the contents to me or anyone else.
You should be wondering whether you can believe me, and whether it's safe to run a program at the behest of a stranger. In general, no, it's not safe and I don't encourage it.
In this case, however, there are a couple of ways for you to decide whether the program is safe without having to trust me. First, you can read it. Unlike an application that you download and click to run, it's transparent, so anyone with the necessary skill can verify what it does.
You may not be able to understand the script yourself. But variations of the script have been posted on this website thousands of times over a period of years. The site is hosted by Apple, which does not allow it to be used to distribute harmful software. Any one of the millions of registered users could have read the script and raised the alarm if it was harmful. Then I would not be here now and you would not be reading this message.
Nevertheless, if you can't satisfy yourself that these instructions are safe, don't follow them. Ask for other options.
4. Here's a summary of what you need to do, if you choose to proceed:
☞ Copy a line of text in this window to the Clipboard.
☞ Paste into the window of another application.
☞ Wait for the test to run. It usually takes a few minutes.
☞ Paste the results, which will have been copied automatically, back into a reply on this page.
The sequence is: copy, paste, wait, paste again. You don't need to copy a second time. Details follow.
5. You may have started the computer in "safe" mode. Preferably, these steps should be taken in “normal” mode, under the conditions in which the problem is reproduced. If the system is now in safe mode and works well enough in normal mode to run the test, restart as usual. If you can only test in safe mode, do that.
6. If you have more than one user, and the one affected by the problem is not an administrator, then please run the test twice: once while logged in as the affected user, and once as an administrator. The results may be different. The user that is created automatically on a new computer when you start it for the first time is an administrator. If you can't log in as an administrator, test as the affected user. Most personal Macs have only one user, and in that case this section doesn’t apply. Don't log in as root.
7. The script is a single long line, all of which must be selected. You can accomplish this easily by triple-clicking anywhere in the line. The whole line will highlight, though you may not see all of it in the browser window, and you can then copy it. If you try to select the line by dragging across the part you can see, you won't get all of it.
Triple-click anywhere in the line of text below on this page to select it:
PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/libexec;clear;cd;p=(Software Hardware Memory Diagnostics Power FireWire Thunderbolt USB Fonts SerialATA 4 1000 25 5120 KiB/s 1024 85 \\b%% 20480 1 MB/s 25000 ports ' com.clark.\* \*dropbox \*GoogleDr\* \*k.AutoCAD\* \*k.Maya\* vidinst\* ' DYLD_INSERT_LIBRARIES\ DYLD_LIBRARY_PATH -86 "` route -n get default|awk '/e:/{print $2}' `" 25 N\\/A down up 102400 25600 recvfrom sendto CFBundleIdentifier 25 25 25 1000 MB com.apple.AirPortBaseStationAgent 464843899 51 5120 files );N5=${#p[@]};p[N5]=` networksetup -listnetworkserviceorder|awk ' NR>1 { sub(/^$[0-9]+$ /,"");n=$0;getline;} $NF=="'${p[26]}')" { sub(/.$/,"",$NF);print n;exit;} ' `;f=('\n%s: %s\n' '\n%s\n\n%s\n' '\nRAM details\n%s\n' %s\ %s '%s\n-\t%s\n' );S0() { echo ' { q=$NF+0;$NF="";u=$(NF-1);$(NF-1)="";gsub(/^ +| +$/,"");if(q>='${p[$1]}') printf("%s (UID %s) is using %s '${p[$2]}'",$0,u,q);} ';};s=(' /^ *$|CSConfigDot/d;s/^ */ /;s/[-0-9A-Fa-f]{22,}/UUID/g;s/(ochat)\.[^.]+(\..+)/\1\2/;/Shared/!s/\/Users\/[^/]+/~/g ' ' s/^ +//;/de: S|[nst]:/p;' ' {sub(/^ +/,"")};/er:/;/y:/&&$2<'${p[10]} ' 1s/://;3,6d;/[my].+:/d;s/^ {4}//;H;${ g;s/\n$//;/s: [^EO]|x([^08]|02[^F]|8[^0])/p;} ' ' 5h;6{ H;g;/P/!p;} ' ' ($1~/^Cy/&&$3>'${p[11]}')||($1~/^Cond/&&$2!~/^N/) ' ' /:$/{ N;/:.+:/d;s/ *://;b0'$'\n'' };/^ *(V.+ [0N]|Man).+ /{ s/ 0x.... //;s/[()]//g;s/(.+: )(.+)/ (\2)/;H;};$b0'$'\n'' d;:0'$'\n'' x;s/\n\n//;/Apple[ ,]|Genesy|Intel|SMSC/d;s/\n.*//;/\)$/p;' ' s/^.*C/C/;H;${ g;/No th|pms/!p;} ' '/= [^GO]/p' '{$1=""};1' ' /Of/!{ s/^.+is |\.//g;p;} ' ' $0&&!/ / { n++;print;} END { if(n<200) print "com.apple.";} ' ' $3~/[0-9]:[0-9]{2}$/ { gsub(/:[0-9:a-f]{14}/,"");} { print|"tail -n'${p[12]}'";} ' ' NR==2&&$4<='${p[13]}' { print $4;} ' ' END { $2/=256;if($2>='${p[15]}') print int($2) } ' ' NR!=13{next};{sub(/[+-]$/,"",$NF)};'"`S0 21 22`" 'NR!=2{next}'"`S0 37 17`" ' NR!=5||$8!~/[RW]/{next};{ $(NF-1)=$1;$NF=int($NF/10000000);for(i=1;i<=3;i++){$i="";$(NF-1-i)="";};};'"`S0 19 20`" 's:^:/:p' '/\.kext\/(Contents\/)?Info\.plist$/p' 's/^.{52}(.+) <.+/\1/p' ' /Launch[AD].+\.plist$/ { n++;print;} END { print "'${p[41]}'";if(n<200) print "/System/";} ' '/\.xpc\/(Contents\/)?Info\.plist$/p' ' NR>1&&!/0x|\.[0-9]+$|com\.apple\.launchctl\.(Aqua|Background|System)$|'${p[41]}'/ { print $3;} ' ' /\.(framew|lproj)|\):/d;/plist:|:.+(Mach|scrip)/s/:[^:]+//p ' '/^root$/p' ' !/\/Contents\/.+\/Contents|Applic|Autom|Frameworks/&&/Lib.+\/Info.plist$/ { n++;print;} END { if(n<1100) print "/System/";} ' '/^\/usr\/lib\/.+dylib$/p' ' /Temp|emac/{next};/(etc|Preferences|Launch[AD].+)\// { sub(".(/private)?","");n++;print;} END { print "'${p[41]}'.plist\t'${p[42]}'";if(n<500) print "Launch";} ' ' /\/(Contents\/.+\/Contents|Frameworks)\/|\.wdgt\/.+\.([bw]|plu)/d;p;' 's/\/(Contents\/)?Info.plist$//;p' ' { gsub("^| |\n","\\|\\|kMDItem'${p[35]}'=");sub("^...."," ") };1 ' p '{print $3"\t"$1}' 's/\'$'\t''.+//p' 's/1/On/p' '/Prox.+: [^0]/p' '$2>'${p[43]}'{$2=$2-1;print}' ' BEGIN { i="'${p[26]}'";M1='${p[16]}';M2='${p[18]}';M3='${p[31]}';M4='${p[32]}';} !/^A/{next};/%/ { getline;if($5<M1) a="user "$2"%, system "$4"%";} /disk0/&&$4>M2 { b=$3" ops/s, "$4" blocks/s";} $2==i { if(c) { d=$3+$4+$5+$6;next;};if($4>M3||$6>M4) c=int($4/1024)" in, "int($6/1024)" out";} END { if(a) print "CPU: "a;if(b) print "I/O: "b;if(c) print "Net: "c" (KiB/s)";if(d) print "Net errors: "d" packets/s";} ' ' /r\[0\] /&&$NF!~/^1(0|72\.(1[6-9]|2[0-9]|3[0-1])|92\.168)\./ { print $NF;exit;} ' ' !/^T/ { printf "(static)";exit;} ' '/apsd|BKAg|OpenD/!s/:.+//p' ' (/k:/&&$3!~/(255\.){3}0/ )||(/v6:/&&$2!~/A/ ) ' ' $1~"lR"&&$2<='${p[25]}';$1~"li"&&$3!~"wpa2";' ' BEGIN { FS=":";p="uniq -c|sed -E '"'s/ +\$[0-9]+\$\$.+\$/\\\2 x\\\1/;s/x1$//'"'";} { n=split($3,a,".");sub(/_2[01].+/,"",$3);print $2" "$3" "a[n]$1|p;b=b$1;} END { close(p);if(b) print("\n\t* Code injection");} ' ' NR!=4{next} {$NF/=10240} '"`S0 27 14`" ' END { if($3~/[0-9]/)print$3;} ' ' BEGIN { L='${p[36]}';} !/^[[:space:]]*(#.*)?$/ { l++;if(l<=L) f=f"\n "$0;} END { F=FILENAME;if(!F) exit;if(!f) f="\n [N/A]";"file -b "F|getline T;if(T!~/^(AS.+ (En.+ )?text$|(Bo|PO).+ sh.+ text ex)/) F=F" ("T")";printf("\nContents of %s\n%s\n",F,f);if(l>L) printf("\n ...and %s more line(s)\n",l-L);} ' ' s/^ ?n...://p;s/^ ?p...:/-'$'\t''/p;' 's/0/Off/p' ' END{print NR} ' ' /id: N|te: Y/{i++} END{print i} ' ' / / { print "'"${p[28]}"'";exit;};1;' '/ en/!s/\.//p' ' NR!=13{next};{sub(/[+-M]$/,"",$NF)};'"`S0 39 40`" ' $10~/\(L/&&$9!~"localhost" { sub(/.+:/,"",$9);print $1": "$9;} ' '/^ +r/s/.+"(.+)".+/\1/p' 's/(.+\.wdgt)\/(Contents\/)?Info\.plist$/\1/p' 's/^.+\/(.+)\.wdgt$/\1/p' ' /l: /{ /DVD/d;s/.+: //;b0'$'\n'' };/s: /{ /V/d;s/^ */- /;H;};$b0'$'\n'' d;:0'$'\n'' x;/APPLE [^:]+$/d;p;' ' /^find: /d;p;' "`S0 44 45`" ' BEGIN{FS="= "} /Path/{print $2} ' );c1=(system_profiler pmset\ -g nvram fdesetup find syslog df vm_stat sar ps sudo\ crontab sudo\ iotop top pkgutil 'PlistBuddy 2>&1 -c "Print' whoami cksum kextstat launchctl sudo\ launchctl crontab 'sudo defaults read' stat lsbom mdfind ' for i in ${p[24]};do ${c1[18]} ${c2[27]} $i;done;' defaults\ read scutil sudo\ dtrace sudo\ profiles sed\ -En awk /S*/*/P*/*/*/C*/*/airport networksetup mdutil sudo\ lsof test osascript\ -e );c2=(com.apple.loginwindow\ LoginHook '" /L*/P*/loginw*' "'tell app \"System Events\" to get properties of login items'|tr , \\\n" 'L*/Ca*/com.ap*.Saf*/E*/* -d 1 -name In*t -exec '"${c1[14]}"' :CFBundleDisplayName" {} \;|sort|uniq' '~ $TMPDIR.. $ -flags +sappnd,schg,uappnd,uchg -o ! -user $UID -o ! -perm -600 $' '.??* -path .Trash -prune -o -type d -name *.app -print -prune' :${p[35]}\" :Label\" '{/,}L*/{Con,Pref}* -type f ! -size 0 -name *.plist -exec plutil -s {} \;' "-f'%N: %l' Desktop L*/Keyc*" therm sysload boot-args status " -F '\$Time \$Message' -k Sender kernel -k Message Req 'bad |Beac|caug|dead[^bl]|FAIL|fail|GPU |hfs: Ru|inval|jnl:|last value [1-9]|n Cause: -|NVDA$|pagin|proc: t|Roamed|rror|ssert|Thrott|tim(ed? ?|ing )o|WARN' -k Message Rne 'Goog|ksadm|SMC:| VALI|xpma' -o -k Sender fseventsd -k Message Req 'SL' " '-du -n DEV -n EDEV 1 10' 'acrx -o comm,ruid,%cpu' '-t1 10 1' '-f -pfc /var/db/r*/com.apple.*.{BS,Bas,Es,J,OSXU,Rem,up}*.bom' '{/,}L*/Lo*/Diag* -type f -regex .\*[cgh] ! -name *ag \( -exec grep -lq "^Thread c" {} \; -exec printf \* \; -o -true $ -execdir stat -f:%Sc:%N -t%F {} \;|sort -t: -k2 |tail -n'${p[38]} '-L {/{S*/,},}L*/Lau* -type f' '-L /{S*/,}L*/StartupItems -type f -exec file {} +' '-L /S*/L*/{C*/Sec*A,E}* {/,}L*/{A*d,Ca*/*/Ex,Co{mpon,reM},Ex,Inter,iTu*/*P,Keyb,Mail/B,Pr*P,Qu*T,Scripti,Sec,Servi,Spo,Widg}* -path \\*s/Resources -prune -o -type f -name Info.plist' '/usr/lib -type f -name *.dylib' `awk "${s[31]}"<<<${p[23]}` "/e*/{auto,{cron,fs}tab,hosts,{[lp],sy}*.conf,pam.d/*,ssh{,d}_config,*.local} {,/usr/local}/etc/periodic/*/* /L*/P*{,/*}/com.a*.{Bo,sec*.ap}*t /S*/L*/Lau*/*t .launchd.conf" list getenv /Library/Preferences/com.apple.alf\ globalstate --proxy '-n get default' -I --dns -getdnsservers\ "${p[N5]}" -getinfo\ "${p[N5]}" -P -m\ / '' -n1 '-R -l1 -n1 -o prt -stats command,uid,prt' '--regexp --only-files --files com.apple.pkg.*|sort|uniq' -kl -l -s\ / '-R -l1 -n1 -o mem -stats command,uid,mem' '+c0 -i4TCP:0-1023' com.apple.dashboard\ layer-gadgets '-d /L*/Mana*/$USER&&echo On' '-app Safari WebKitDNSPrefetchingEnabled' "+c0 -l|awk '{print(\$1,\$3)}'|sort|uniq -c|sort -n|tail -1|awk '{print(\$2,\$3,\$1)}'" );N1=${#c2[@]};for j in {0..9};do c2[N1+j]=SP${p[j]}DataType;done;N2=${#c2[@]};for j in 0 1;do c2[N2+j]="-n ' syscall::'${p[33+j]}':return { @out[execname,uid]=sum(arg0) } tick-10sec { trunc(@out,1);exit(0);} '";done;l=(Restricted\ files Hidden\ apps 'Elapsed time (s)' POST Battery Safari\ extensions Bad\ plists 'High file counts' User Heat System\ load boot\ args FileVault Diagnostic\ reports Log 'Free space (MiB)' 'Swap (MiB)' Activity 'CPU per process' Login\ hook 'I/O per process' Mach\ ports kexts Daemons Agents launchd Startup\ items Admin\ access Root\ access Bundles dylibs Apps Font\ issues Inserted\ dylibs Firewall Proxies DNS TCP/IP Wi-Fi Profiles Root\ crontab User\ crontab 'Global login items' 'User login items' Spotlight Memory Listeners Widgets Parental\ Controls Prefetching SATA Descriptors );N3=${#l[@]};for i in 0 1 2;do l[N3+i]=${p[5+i]};done;N4=${#l[@]};for j in 0 1;do l[N4+j]="Current ${p[29+j]}stream data";done;A0() { id -G|grep -qw 80;v[1]=$?;((v[1]==0))&&sudo true;v[2]=$?;v[3]=`date +%s`;clear >&-;date '+Start time: %T %D%n';};for i in 0 1;do eval ' A'$((1+i))'() { v=` eval "${c1[$1]} ${c2[$2]}"|'${c1[30+i]}' "${s[$3]}" `;[[ "$v" ]];};A'$((3+i))'() { v=` while read i;do [[ "$i" ]]&&eval "${c1[$1]} ${c2[$2]}" \"$i\"|'${c1[30+i]}' "${s[$3]}";done<<<"${v[$4]}" `;[[ "$v" ]];};A'$((5+i))'() { v=` while read i;do '${c1[30+i]}' "${s[$1]}" "$i";done<<<"${v[$2]}" `;[[ "$v" ]];};';done;A7(){ v=$((`date +%s`-v[3]));};B2(){ v[$1]="$v";};for i in 0 1;do eval ' B'$i'() { v=;((v['$((i+1))']==0))||{ v=No;false;};};B'$((3+i))'() { v[$2]=`'${c1[30+i]}' "${s[$3]}"<<<"${v[$1]}"`;} ';done;B5(){ v[$1]="${v[$1]}"$'\n'"${v[$2]}";};B6() { v=` paste -d: <(printf "${v[$1]}") <(printf "${v[$2]}")|awk -F: ' {printf("'"${f[$3]}"'",$1,$2)} ' `;};B7(){ v=`grep -Fv "${v[$1]}"<<<"$v"`;};C0(){ [[ "$v" ]]&&echo "$v";};C1() { [[ "$v" ]]&&printf "${f[$1]}" "${l[$2]}" "$v";};C2() { v=`echo $v`;[[ "$v" != 0 ]]&&C1 0 $1;};C3() { v=`sed -E "$s"<<<"$v"`&&C1 1 $1;};for i in 1 2;do for j in 0 2 3;do eval D$i$j'(){ A'$i' $1 $2 $3; C'$j' $4;};';done;done;{ A0;D20 0 $((N1+1)) 2;D10 0 $N1 1;B0;C2 27;B0&&! B1&&C2 28;D12 15 37 25 8;A1 0 $((N1+2)) 3;C0;D13 0 $((N1+3)) 4 3;D23 0 $((N1+4)) 5 4;D13 0 $((N1+9)) 59 50;for i in 0 1 2;do D13 0 $((N1+5+i)) 6 $((N3+i));done;D13 1 10 7 9;D13 1 11 8 10;D22 2 12 9 11;D12 3 13 10 12;D23 4 19 44 13;D23 5 14 12 14;D22 6 36 13 15;D22 7 37 14 16;D23 8 15 38 17;D22 9 16 16 18;B1&&{ D22 35 49 61 51;D22 11 17 17 20;for i in 0 1;do D22 28 $((N2+i)) 45 $((N4+i));done;};D22 12 44 54 45;D22 12 39 15 21;A1 13 40 18;B2 4;B3 4 0 19;A3 14 6 32 0;B4 0 5 11;A1 17 41 20;B7 5;C3 22;B4 4 6 21;A3 14 7 32 6;B4 0 7 11;B3 4 0 22;A3 14 6 32 0;B4 0 8 11;B5 7 8;B1&&{ A2 19 26 23;B7 7;C3 23;};A2 18 26 23;B7 7;C3 24;A2 4 20 21;B7 6;B2 9;A4 14 7 52 9;B2 10;B6 9 10 4;C3 25;D13 4 21 24 26;B4 4 12 26;B3 4 13 27;A1 4 22 29;B7 12;B2 14;A4 14 6 52 14;B2 15;B6 14 15 4;B3 0 0 30;C3 29;A1 4 23 27;B7 13;C3 30;D13 24 24 32 31;D13 25 37 32 33;A2 23 18 28;B2 16;A2 16 25 33;B7 16;B3 0 0 34;B2 21;A6 47 21&&C0;B1&&{ D13 21 0 32 19;D13 10 42 32 40;D22 29 35 46 39;};D23 14 1 62 42;D12 34 43 53 44;D22 0 $((N1+8)) 51 32;D13 4 8 41 6;D12 26 28 35 34;D13 27 29 36 35;A2 27 32 39&&{ B2 19;A2 33 33 40;B2 20;B6 19 20 3;};C2 36;D23 33 34 42 37;B1&&D23 35 45 55 46;D23 32 31 43 38;D12 36 47 32 48;D13 20 42 32 41;D13 37 2 48 43;D13 4 5 32 1;D13 4 3 60 5;D12 26 48 49 49;B3 4 22 57;A1 26 46 56;B7 22;B3 0 0 58;C3 47;D22 4 4 50 0;D23 22 9 37 7;A7;C2 2;} 2>/dev/null|pbcopy;exit 2>&-
Copy the selected text to the Clipboard by pressing the key combination command-C.
8. Launch the built-in Terminal application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.
Click anywhere in the Terminal window and paste by pressing command-V. The text you pasted should vanish immediately. If it doesn't, press the return key.
9. If you see an error message in the Terminal window such as "Syntax error" or "Event not found," enter
exec bash
and press return. Then paste the script again.
10. If you're logged in as an administrator, you'll be prompted for your login password. Nothing will be displayed when you type it. You will not see the usual dots in place of typed characters. Make sure caps lock is off. Type carefully and then press return. You may get a one-time warning to be careful. If you make three failed attempts to enter the password, the test will run anyway, but it will produce less information. In most cases, the difference is not important. If you don't know the password, or if you prefer not to enter it, press the key combination control-C or just press return three times at the password prompt. Again, the script will still run.
If you're not logged in as an administrator, you won't be prompted for a password. The test will still run. It just won't do anything that requires administrator privileges.
11. The test may take a few minutes to run, depending on how many files you have and the speed of the computer. A computer that's abnormally slow may take longer to run the test. While it's running, there will be nothing in the Terminal window and no indication of progress. Wait for the line
[Process completed]
to appear. If you don't see it within half an hour or so, the test probably won't complete in a reasonable time. In that case, close the Terminal window and report what happened. No harm will be done.
12. When the test is complete, quit Terminal. The results will have been copied to the Clipboard automatically. They are not shown in the Terminal window. Please don't copy anything from there. All you have to do is start a reply to this comment and then paste by pressing command-V again.
At the top of the results, there will be a line that begins with the words "Start time." If you don't see that, but instead see a mass of gibberish, you didn't wait for the "Process completed" message to appear in the Terminal window. Please wait for it and try again.
If any private information, such as your name or email address, appears in the results, anonymize it before posting. Usually that won't be necessary.
13. When you post the results, you might see an error message on the web page: "You have included content in your post that is not permitted," or "You are not authorized to post." That's a bug in the forum software. Please post the test results on Pastebin, then post a link here to the page you created.
14. This is a public forum, and others may give you advice based on the results of the test. They speak only for themselves, and I don't necessarily agree with them.
Copyright © 2014 by Linc Davis. As the sole author of this work, I reserve all rights to it except as provided in the Use Agreement for the Apple Support Communities website ("ASC"). Readers of ASC may copy it for their own personal use. Neither the whole nor any part may be redistributed.

HT5290 Hi, I would like to get virus protection for my Mac Air

Hi,
I would like to get my Virus Protection installed for my MAC Air.

The linked article is 6 years old. That doesn't necessarily mean it's no longer relevant, but it is out-of-date in terms of current tecvhnology.
Some people are fervently oppsoed to using AV software on a Mac. Some people believe it's not a bad idea to run AV software on a Mac so long as it's not Nortons, McAfee, or other bloatware (such as MacKeeper which has its own threads, and is often mentioned in AV threads as well). If you search through Apple Discussions, you can find hours of reading on this subject.
ClamXav and Sophos, in my experience, are not going to kill your system, and allow you to consider the possibility that there could be an OS X malware issue at some point in the near or distant future. You're not crazy or killing your system if you run one of these two apps. You're also not crazy if you use no AV software on OS X.
But seriously, there are hundreds, maybe thousands of posts about this on Apple Discussions. Take a look for yourself, and whatever you decide, you;re not crazy.

Does my new apple mac air come with anti-virus?

does the new mac air come with anti-virus?

1. This is a comment on what you should and should not do to protect yourself from malicious software ("malware") that circulates on the Internet. It does not apply to software, such as keystroke loggers, that may be installed deliberately by an intruder who has hands-on access to the victim's computer. That threat is in a different category, and there's no easy way to defend against it. If you have reason to suspect that you're the target of such an attack, you need expert help.
If you find this comment too long or too technical, read only sections 5, 6, and 10.
OS X now implements three layers of built-in protection specifically against malware, not counting runtime protections such as execute disable, sandboxing, system library randomization, and address space layout randomization that may also guard against other kinds of exploits.
2. All versions of OS X since 10.6.7 have been able to detect known Mac malware in downloaded files, and to block insecure web plugins. This feature is transparent to the user, but internally Apple calls it "XProtect." The malware recognition database is automatically checked for updates once a day; however, you shouldn't rely on it, because the attackers are always at least a day ahead of the defenders.
The following caveats apply to XProtect:
It can be bypassed by some third-party networking software, such as BitTorrent clients and Java applets.
It only applies to software downloaded from the network. Software installed from a CD or other media is not checked.
As new versions of OS X are released, it's not clear whether Apple will indefinitely continue to maintain the XProtect database of older versions such as 10.6. The security of obsolete system versions may eventually be degraded. Security updates to the code of obsolete systems will stop being released at some point, and that may leave them open to other kinds of attack besides malware.
3. Starting with OS X 10.7.5, there has been a second layer of built-in malware protection, designated "Gatekeeper" by Apple. By default, applications and Installer packages downloaded from the network will only run if they're digitally signed by a developer with a certificate issued by Apple. Software certified in this way hasn't necessarily been tested by Apple, but you can be reasonably sure that it hasn't been modified by anyone other than the developer. His identity is known to Apple, so he could be held legally responsible if he distributed malware. That may not mean much if the developer lives in a country with a weak legal system (see below.)
Gatekeeper doesn't depend on a database of known malware. It has, however, the same limitations as XProtect, and in addition the following:
It can easily be disabled or overridden by the user.
A malware attacker could get control of a code-signing certificate under false pretenses, or could simply ignore the consequences of distributing codesigned malware.
An App Store developer could find a way to bypass Apple's oversight, or the oversight could fail due to human error.
For the reasons given above, App Store products, and other applications recognized by Gatekeeper as signed, are safer than others, but they can't be considered absolutely safe. "Sandboxed" applications may prompt for access to private data, such as your contacts, or for access to the network. Think before granting that access. Sandboxing security is based on user input. Never click through any request for authorization without thinking.
4. Starting with OS X 10.8.3, a third layer of protection has been added: a "Malware Removal Tool" (MRT). MRT runs automatically in the background when you update the OS. It checks for, and removes, malware that may have evaded the other protections via a Java exploit (see below.) MRT also runs when you install or update the Apple-supplied Java runtime (but not the Oracle runtime.) Like XProtect, MRT is effective against known threats, but not against unknown ones. It notifies you if it finds malware, but otherwise there's no user interface to MRT.
5. The built-in security features of OS X reduce the risk of malware attack, but they're not absolute protection. The first and best line of defense is always going to be your own intelligence. With the possible exception of Java exploits, all known malware circulating on the Internet that affects a fully-updated installation of OS X 10.6 or later takes the form of so-called "Trojan horses," which can only have an effect if the victim is duped into running them. The threat therefore amounts to a battle of wits between you and the malware attacker. If you're smarter than he thinks you are, you'll win.
That means, in practice, that you always stay within a safe harbor of computing practices. How do you know what is safe?
Any website that prompts you to install a “codec,” “plug-in,” "player," "extractor," or “certificate” that comes from that same site, or an unknown one, is unsafe.
A web operator who tells you that you have a “virus,” or that anything else is wrong with your computer, or that you have won a prize in a contest you never entered, is trying to commit a crime with you as the victim. (Some reputable websites did legitimately warn visitors who were infected with the "DNSChanger" malware. That exception to this rule no longer applies.)
Pirated copies or "cracks" of commercial software, no matter where they come from, are unsafe.
Software of any kind downloaded from a BitTorrent or from a Usenet binary newsgroup is unsafe.
Software that purports to help you do something that's illegal or that infringes copyright, such as saving streamed audio or video for reuse without permission, is unsafe. All YouTube "downloaders" are outside the safe harbor, though not all are necessarily harmful.
Software with a corporate brand, such as Adobe Flash Player, must be downloaded directly from the developer’s website. If it comes from any other source, it's unsafe. For instance, if a web page warns you that Flash is out of date, do not follow an offered link to an update. Go to the Adobe website to download it, if you need it at all.
Even signed applications, no matter what the source, should not be trusted if they do something unexpected, such as asking for permission to access your contacts, your location, or the Internet for no obvious reason.
"FREE WI-FI !!!" networks in public places are unsafe unless you can verify that the network is not a trap (which you probably can't.) Even then, do not download any software or transmit any private information while connected to such a network, regardless of where it seems to come from or go to.
6. Java on the Web (not to be confused with JavaScript, to which it's not related, despite the similarity of the names) is a weak point in the security of any system. Java is, among other things, a platform for running complex applications in a web page, on the client. That was always a bad idea, and Java's developers have proven themselves incapable of implementing it without also creating a portal for malware to enter. Past Java exploits are the closest thing there has ever been to a Windows-style virus affecting OS X. Merely loading a page with malicious Java content could be harmful.
Fortunately, client-side Java on the Web is obsolete and mostly extinct. Only a few outmoded sites still use it. Try to hasten the process of extinction by avoiding those sites, if you have a choice. Forget about playing games or other non-essential uses of Java.
Java is not included in OS X 10.7 and later. Discrete Java installers are distributed by Apple and by Oracle (the developer of Java.) Don't use either one unless you need it. Most people don't. If Java is installed, disable it — not JavaScript — in your browsers.
Regardless of version, experience has shown that Java on the Web can't be trusted. If you must use a Java applet for a task on a specific site, enable Java only for that site in Safari. Never enable Java for a public website that carries third-party advertising. Use it only on well-known, login-protected, secure websites without ads. In Safari 6 or later, you'll see a lock icon in the address bar with the abbreviation "https" when visiting a secure site.
Follow the above guidelines, and you’ll be as safe from malware as you can practically be. The rest of this comment concerns what you should not do to protect yourself.
7. Never install any commercial "anti-virus" or "Internet security" products for the Mac, as they all do more harm than good, if they do any good at all. Any database of known threats is always going to be out of date. Most of the danger is from unknown threats. If you need to be able to detect Windows malware in your files, use one of the free anti-virus products in the Mac App Store — nothing else.
Why shouldn't you use commercial "anti-virus" products?
Their design is predicated on the nonexistent threat that malware may be injected at any time, anywhere in the file system. Malware is downloaded from the network; it doesn't materialize from nowhere.
In order to meet that nonexistent threat, the software modifies or duplicates low-level functions of the operating system, which is a waste of resources and a common cause of instability, bugs, and poor performance.
To recognize malware, the software depends on a database of known threats, which is always at least a day out of date. Most of the real danger comes from highly targeted "zero-day" attacks that are not yet recognized.
By modifying the operating system, the software itself may create weaknesses that could be exploited by malware attackers.
8. An anti-malware product from the App Store, such as "ClamXav," doesn't have these drawbacks. That doesn't mean it's entirely safe. It may report email messages that have "phishing" links in the body, or Windows malware in attachments, as infected files, and offer to delete or move them. Doing so will corrupt the Mail database. The messages should be deleted from within the Mail application.
An anti-virus app is not needed, and should not be relied upon, for protection against OS X malware. It's useful only for detecting Windows malware. Windows malware can't harm you directly (unless, of course, you use Windows.) Just don't pass it on to anyone else.
A Windows malware attachment in email is usually easy to recognize. The file name will often be targeted at people who aren't very bright; for example:
♥♥♥♥♥♥♥♥♥♥♥♥♥♥!!!!!!!H0TBABEZ4U!!!!!!!.AVI♥♥♥♥♥♥♥♥♥♥♥♥♥♥.exe
Anti-virus software may be able to tell you which particular trojan it is, but do you care? In practice, there's seldom a reason to use the software unless an institutional policy requires it.
The ClamXav developer won't try to "upsell" you to a paid version of the product. Other developers may do that. Don't be upsold. For one thing, you should not pay to protect Windows users from the consequences of their choice of computing platform. For another, a paid upgrade from a free app will probably have the disadvantages mentioned in section 7.
9. It seems to be a common belief that the built-in Application Firewall acts as a barrier to infection, or prevents malware from functioning. It does neither. It blocks inbound connections to certain network services you're running, such as file sharing. It's disabled by default and you should leave it that way if you're behind a router on a private home or office network. Activate it only when you're on an untrusted network, for instance a public Wi-Fi hotspot, where you don't want to provide services. Disable any services you don't use in the Sharing preference pane. All are disabled by default.
10. As a Mac user you don't have to live in fear that your computer may be infected every time you install software, read email, or visit a web page. But neither should you assume that you will always be safe from exploitation, no matter what you do. The greatest harm done by security software is precisely its selling point: it makes people feel safe. They may then feel safe enough to take risks from which the software doesn't protect them. Nothing can lessen the need for safe computing practices.

I am going to buy either a Mac Air or Mac Pro Retina 8GB RAM and 256GB. And as I have to still run Windows I will install Parallels 9. As the Mac are both 64bit machines does that mean I need to install Windows 7 64bit ? And office pro 2013 64 bit too?

I am going to buy either a Mac Air or Mac Pro Retina 8GB RAM and 256GB. And as I have to still run Windows programs I will install Parallels 9. As the Mac are both 64bit machines does that mean I need to install Windows 7 64bit or just install 32 bit? (Going with Win7 as I hate Win8). And I will install Office Pro 2013 64 bit too or 32 bit or is that automatically selected by the underlying OS (I use Word, Excel and Access mainly for a membership database of a local club) ? I am not a power user so would appreciate advice on way to go

Again thank you. If I only use word, excel and access in the Win environment and Mac OS for email and safari for internet do I need anti virus software . Ie my connection to the world is mac only and I use office pro only to ruin the club, newsletters, membership database etc. and of course anything I do there can drag/drop to the mac environ to email. That's my understanding anyway. Next will my existing .pst file copy directly into mac mail or do I have to runs translator as I recall reading something about that ages ago when I started thinking Mac

Some one has blocked Safari on my Mac Air for 'security reasons'

Someone has blocked Safari on my Mac air " for security" temporarily the same message came up on my iPhone 6 Plus but is now gone. Need to remove the block from my computer

Helpful Links Regarding Malware Problems
If you are having an immediate problem with ads popping up see The Safe Mac » Adware Removal Guide, remove adware that displays pop-up ads and graphics on your Mac, and AdwareMedic. If you require anti-virus protection Thomas Reed recommends using ClamXAV. (Thank you to Thomas Reed for this recommendation.) You might consider adding this Safari extensions: Adblock Plus 1.8.9.
Open Safari, select Preferences from the Safari menu. Click on Extensions icon in the toolbar. Disable all Extensions. If this stops your problem, then re-enable them one by one until the problem returns. Now remove that extension as it is causing the problem.
The following comes from user stevejobsfan0123. I have made minor changes to adapt to this presentation.
Fix Some Browser Pop-ups That Take Over Safari.
Common pop-ups include a message saying the government has seized your computer and you must pay to have it released (often called "Moneypak"), or a phony message saying that your computer has been infected, and you need to call a tech support number (sometimes claiming to be Apple) to get it resolved. First, understand that these pop-ups are not caused by a virus and your computer has not been affected. This "hijack" is limited to your web browser. Also understand that these messages are scams, so do not pay any money, call the listed number, or provide any personal information. This article will outline the solution to dismiss the pop-up.
Quit Safari
Usually, these pop-ups will not go away by either clicking "OK" or "Cancel." Furthermore, several menus in the menu bar may become disabled and show in gray, including the option to quit Safari. You will likely have to force quit Safari. To do this, press Command + option + esc, select Safari, and press Force Quit.
Relaunch Safari
If you relaunch Safari, the page will reopen. To prevent this from happening, hold down the 'Shift' key while opening Safari. This will prevent windows from the last time Safari was running from reopening.
This will not work in all cases. The shift key must be held at the right time, and in some cases, even if done correctly, the window reappears. In these circumstances, after force quitting Safari, turn off Wi-Fi or disconnect Ethernet, depending on how you connect to the Internet. Then relaunch Safari normally. It will try to reload the malicious webpage, but without a connection, it won't be able to. Navigate away from that page by entering a different URL, i.e. www.apple.com, and trying to load it. Now you can reconnect to the Internet, and the page you entered will appear rather than the malicious one.

How to uninstall antivirus program on Mac Air please

Hi I have Mac Air OS X 10.9.4 and wanted to download McAfee antivirus program which requires removing my now defunct Sophos Antivirus. I have removed all Sophos files (per my computer) into the trash but still am told McAfee cannot download because there is still an old incompatible antivirus program. Please help. I am now unprotected. There is a Sophos "logo" in the tool bar but I don't know how to remove it...and it will not function when opened. Thanks much!

From Removal tools for Sophos Anti-Virus for Mac:
In some situations you may be unable to run the built-in Sophos Anti-Virus for Mac (SAV for Mac) uninstaller. This article provides a standalone tool to remove the installation of Sophos Anti-Virus for Mac
Common reasons for needing this tool are:
If the product has been deleted (e.g., dragged to the Trash) rather than correctly uninstalled.
Where the uninstaller is unable to run due to a corrupted receipt file.
Download, expand, and run the applicable uninstaller for the Sophos product you installed.
Do not install McAfee.

Why can't McAfee Antivirus download onto OS X Yosemite, Mac Air?

Hello, I am trying to download McAfee Antivirus on my 2008 Mac Air with OS X Yosemite and am repeatedly told antivirus is already installed. McAfee Tech could not find any apps indicating such. Any ideas appreciated. I got a message from a medical institution saying my Mac had a virus so am of course concerned...Thank you!

Mac users often ask whether they should install "anti-virus" (AV) software. The usual answer is "no." That answer is right, but it may give the wrong impression that there is no threat from what are loosely called "viruses." There is a threat, and you need to educate yourself about it.
1. This is a comment on what you should—and should not—do to protect yourself from malicious software ("malware") that circulates on the Internet and gets onto a computer as an unintended consequence of the user's actions. It does not apply to software, such as keystroke loggers, that may be installed deliberately by an intruder who has hands-on access to the computer, or who has been able to take control of it remotely. That threat is in a different category, and there's no easy way to defend against it. AV software is not intended to, and does not, afford any protection against such attacks.
The comment is long because the issue is complex. The key points are in sections 5, 6, and 10.
OS X now implements three layers of built-in protection specifically against malware, not counting runtime protections such as execute disable, sandboxing, system library randomization, and address space layout randomization that may also guard against other kinds of exploits.
2. All versions of OS X since 10.6.7 have been able to detect known Mac malware in downloaded files, and to block insecure web plugins. This feature is transparent to the user. Internally Apple calls it "XProtect."
The malware recognition database used by XProtect is automatically updated; however, you shouldn't rely on it, because the attackers are always at least a day ahead of the defenders.
The following caveats apply to XProtect:
☞ It can be bypassed by some third-party networking software, such as BitTorrent clients and Java applets.
☞ It only applies to software downloaded from the network. Software installed from a CD or other media is not checked.
As new versions of OS X are released, it's not clear whether Apple will indefinitely continue to maintain the XProtect database of older versions such as 10.6. The security of obsolete system versions may eventually be degraded. Security updates to the code of obsolete systems will stop being released at some point, and that may leave them open to other kinds of attack besides malware.
3. Starting with OS X 10.7.5, there has been a second layer of built-in malware protection, designated "Gatekeeper" by Apple. By default, applications and Installer packages downloaded from the network will only run if they're digitally signed by a developer with a certificate issued by Apple. Software certified in this way hasn't necessarily been tested by Apple, but you can be reasonably sure that it hasn't been modified by anyone other than the developer. His identity is known to Apple, so he could be held legally responsible if he distributed malware. That may not mean much if the developer lives in a country with a weak legal system (see below.)
Gatekeeper doesn't depend on a database of known malware. It has, however, the same limitations as XProtect, and in addition the following:
☞ It can easily be disabled or overridden by the user.
☞ A malware attacker could get control of a code-signing certificate under false pretenses, or could simply ignore the consequences of distributing codesigned malware.
☞ An App Store developer could find a way to bypass Apple's oversight, or the oversight could fail due to human error.
Apple has taken far too long to revoke the codesigning certificates of some known abusers, thereby diluting the value of Gatekeeper and the Developer ID program. Those lapses don't involve App Store products, however.
For the reasons given, App Store products, and—to a lesser extent—other applications recognized by Gatekeeper as signed, are safer than others, but they can't be considered absolutely safe. "Sandboxed" applications may prompt for access to private data, such as your contacts, or for access to the network. Think before granting that access. Sandbox security is based on user input. Never click through any request for authorization without thinking.
4. Starting with OS X 10.8.3, a third layer of protection has been added: a "Malware Removal Tool" (MRT). MRT runs automatically in the background when you update the OS. It checks for, and removes, malware that may have evaded the other protections via a Java exploit (see below.) MRT also runs when you install or update the Apple-supplied Java runtime (but not the Oracle runtime.) Like XProtect, MRT is effective against known threats, but not against unknown ones. It notifies you if it finds malware, but otherwise there's no user interface to MRT.
5. The built-in security features of OS X reduce the risk of malware attack, but they are not, and never will be, complete protection. Malware is a problem of human behavior, not machine behavior, and no technological fix alone is going to solve it. Trusting software to protect you will only make you more vulnerable.
The best defense is always going to be your own intelligence. With the possible exception of Java exploits, all known malware circulating on the Internet that affects a fully-updated installation of OS X 10.6 or later takes the form of so-called "Trojan horses," which can only have an effect if the victim is duped into running them. The threat therefore amounts to a battle of wits between you and Internet criminals. If you're better informed than they think you are, you'll win. That means, in practice, that you always stay within a safe harbor of computing practices. How do you know when you're leaving the safe harbor? Below are some warning signs of danger.
Software from an untrustworthy source
☞ Software with a corporate brand, such as Adobe Flash Player, doesn't come directly from the developer’s website. Do not trust an alert from any website to update Flash, or your browser, or any other software. A genuine alert that Flash is outdated and blocked is shown on this support page. Follow the instructions on the support page in that case. Otherwise, assume that the alert is fake and someone is trying to scam you into installing malware. If you see such alerts on more than one website, ask for instructions.
☞ Software of any kind is distributed via BitTorrent, or Usenet, or on a website that also distributes pirated music or movies.
☞ Rogue websites such as Softonic, Soft32, and CNET Download distribute free applications that have been packaged in a superfluous "installer."
☞ The software is advertised by means of spam or intrusive web ads. Any ad, on any site, that includes a direct link to a download should be ignored.
Software that is plainly illegal or does something illegal
☞ High-priced commercial software such as Photoshop is "cracked" or "free."
☞ An application helps you to infringe copyright, for instance by circumventing the copy protection on commercial software, or saving streamed media for reuse without permission. All "YouTube downloaders" are in this category, though not all are necessarily malicious.
Conditional or unsolicited offers from strangers
☞ A telephone caller or a web page tells you that you have a “virus” and offers to help you remove it. (Some reputable websites did legitimately warn visitors who were infected with the "DNSChanger" malware. That exception to this rule no longer applies.)
☞ A web site offers free content such as video or music, but to use it you must install a “codec,” “plug-in,” "player," "downloader," "extractor," or “certificate” that comes from that same site, or an unknown one.
☞ You win a prize in a contest you never entered.
☞ Someone on a message board such as this one is eager to help you, but only if you download an application of his choosing.
☞ A "FREE WI-FI !!!" network advertises itself in a public place such as an airport, but is not provided by the management.
☞ Anything online that you would expect to pay for is "free."
Unexpected events
☞ A file is downloaded automatically when you visit a web page, with no other action on your part. Delete any such file without opening it.
☞ You open what you think is a document and get an alert that it's "an application downloaded from the Internet." Click Cancel and delete the file. Even if you don't get the alert, you should still delete any file that isn't what you expected it to be.
☞ An application does something you don't expect, such as asking for permission to access your contacts, your location, or the Internet for no obvious reason.
☞ Software is attached to email that you didn't request, even if it comes (or seems to come) from someone you trust.
I don't say that leaving the safe harbor just once will necessarily result in disaster, but making a habit of it will weaken your defenses against malware attack. Any of the above scenarios should, at the very least, make you uncomfortable.
6. Java on the Web (not to be confused with JavaScript, to which it's not related, despite the similarity of the names) is a weak point in the security of any system. Java is, among other things, a platform for running complex applications in a web page, on the client. That was always a bad idea, and Java's developers have proven themselves incapable of implementing it without also creating a portal for malware to enter. Past Java exploits are the closest thing there has ever been to a Windows-style virus affecting OS X. Merely loading a page with malicious Java content could be harmful.
Fortunately, client-side Java on the Web is obsolete and mostly extinct. Only a few outmoded sites still use it. Try to hasten the process of extinction by avoiding those sites, if you have a choice. Forget about playing games or other non-essential uses of Java.
Java is not included in OS X 10.7 and later. Discrete Java installers are distributed by Apple and by Oracle (the developer of Java.) Don't use either one unless you need it. Most people don't. If Java is installed, disable it—not JavaScript—in your browsers.
Regardless of version, experience has shown that Java on the Web can't be trusted. If you must use a Java applet for a task on a specific site, enable Java only for that site in Safari. Never enable Java for a public website that carries third-party advertising. Use it only on well-known, login-protected, secure websites without ads. In Safari 6 or later, you'll see a padlock icon in the address bar when visiting a secure site.
Stay within the safe harbor, and you’ll be as safe from malware as you can practically be. The rest of this comment concerns what you should not do to protect yourself.
7. Never install any commercial AV or "Internet security" products for the Mac, as they are all worse than useless. If you need to be able to detect Windows malware in your files, use one of the free security apps in the Mac App Store—nothing else.
Why shouldn't you use commercial AV products?
☞ To recognize malware, the software depends on a database of known threats, which is always at least a day out of date. This technique is a proven failure, as a major AV software vendor has admitted. Most attacks are "zero-day"—that is, previously unknown. Recognition-based AV does not defend against such attacks, and the enterprise IT industry is coming to the realization that traditional AV software is worthless.
☞ Its design is predicated on the nonexistent threat that malware may be injected at any time, anywhere in the file system. Malware is downloaded from the network; it doesn't materialize from nowhere. In order to meet that nonexistent threat, commercial AV software modifies or duplicates low-level functions of the operating system, which is a waste of resources and a common cause of instability, bugs, and poor performance.
☞ By modifying the operating system, the software may also create weaknesses that could be exploited by malware attackers.
☞ Most importantly, a false sense of security is dangerous.
8. An AV product from the App Store, such as "ClamXav," has the same drawback as the commercial suites of being always out of date, but it does not inject low-level code into the operating system. That doesn't mean it's entirely harmless. It may report email messages that have "phishing" links in the body, or Windows malware in attachments, as infected files, and offer to delete or move them. Doing so will corrupt the Mail database. The messages should be deleted from within the Mail application.
An AV app is not needed, and cannot be relied upon, for protection against OS X malware. It's useful, if at all, only for detecting Windows malware, and even for that use it's not really effective, because new Windows malware is emerging much faster than OS X malware.
Windows malware can't harm you directly (unless, of course, you use Windows.) Just don't pass it on to anyone else. A malicious attachment in email is usually easy to recognize by the name alone. An actual example:
London Terror Moovie.avi [124 spaces] Checked By Norton Antivirus.exe
You don't need software to tell you that's a Windows trojan. Software may be able to tell you which trojan it is, but who cares? In practice, there's no reason to use recognition software unless an organizational policy requires it. Windows malware is so widespread that you should assume it's in every email attachment until proven otherwise. Nevertheless, ClamXav or a similar product from the App Store may serve a purpose if it satisfies an ill-informed network administrator who says you must run some kind of AV application. It's free and it won't handicap the system.
The ClamXav developer won't try to "upsell" you to a paid version of the product. Other developers may do that. Don't be upsold. For one thing, you should not pay to protect Windows users from the consequences of their choice of computing platform. For another, a paid upgrade from a free app will probably have all the disadvantages mentioned in section 7.
9. It seems to be a common belief that the built-in Application Firewall acts as a barrier to infection, or prevents malware from functioning. It does neither. It blocks inbound connections to certain network services you're running, such as file sharing. It's disabled by default and you should leave it that way if you're behind a router on a private home or office network. Activate it only when you're on an untrusted network, for instance a public Wi-Fi hotspot, where you don't want to provide services. Disable any services you don't use in the Sharing preference pane. All are disabled by default.
10. As a Mac user, you don't have to live in fear that your computer may be infected every time you install software, read email, or visit a web page. But neither can you assume that you will always be safe from exploitation, no matter what you do. Navigating the Internet is like walking the streets of a big city. It can be as safe or as dangerous as you choose to make it. The greatest harm done by security software is precisely its selling point: it makes people feel safe. They may then feel safe enough to take risks from which the software doesn't protect them. Nothing can lessen the need for safe computing practices.

Is antivirus necessary on the new Mac Air, need reassurance.

Is an antivirus necessary on the new Mac Air, I need to be sure!

mastertaster wrote:
Is an antivirus necessary on the new Mac Air, I need to be sure!
If you are using OS X as indicated in your profile, you already have it.
OS X already includes everything it needs to protect itself from viruses and malware. Keep it updated with software updates from Apple.
A much better question to ask is "how should I protect my Mac":
Never install any product that claims to "speed up", "clean up", "optimize", or "accelerate" your Mac. Without exception, they will do the opposite.
Never install pirated or "cracked" software, software obtained from dubious websites, or other questionable sources. Illegally obtained software is almost certain to contain malware.
Don’t supply your password in response to a popup window requesting it, unless you know what it is and the reason your credentials are required.
Don’t open email attachments from email addresses that you do not recognize, or click links contained in an email:
Most of these are scams that direct you to fraudulent sites that attempt to convince you to disclose personal information.
Such "phishing" attempts are the 21st century equivalent of a social exploit that has existed since the dawn of civilization. Don’t fall for it.
Apple will never ask you to reveal personal information in an email. If you receive an unexpected email from Apple saying your account will be closed unless you take immediate action, just ignore it. If your iTunes or App Store account becomes disabled for valid reasons, you will know when you try to buy something or log in to this support site, and are unable to.
Don’t install browser extensions unless you understand their purpose. Go to the Safari menu > Preferences > Extensions. If you see any extensions that you do not recognize or understand, simply click the Uninstall button and they will be gone.
Don’t install Java unless you are certain that you need it:
Java, a non-Apple product, is a potential vector for malware. If you are required to use Java, be mindful of that possibility.
Disable Java in Safari > Preferences > Security.
Despite its name JavaScript is unrelated to Java. No malware can infect your Mac through JavaScript. It’s OK to leave it enabled.
Block browser popups: Safari menu > Preferences > Security > and check "Block popup windows":
Popup windows are useful and required for some websites, but popups have devolved to become a common means to deliver targeted advertising that you probably do not want.
Popups themselves cannot infect your Mac, but many contain resource-hungry code that will slow down Internet browsing.
If you ever see a popup indicating it detected registry errors, that your Mac is infected with some ick, or that you won some prize, it is 100% fraudulent. Ignore it.
Ignore hyperventilating popular media outlets that thrive by promoting fear and discord with entertainment products arrogantly presented as "news". Learn what real threats actually exist and how to arm yourself against them:
The most serious threat to your data security is phishing. To date, most of these attempts have been pathetic and are easily recognized, but that is likely to change in the future as criminals become more clever.
OS X viruses do not exist, but intentionally malicious or poorly written code, created by either nefarious or inept individuals, is nothing new.
Never install something without first knowing what it is, what it does, how it works, and how to get rid of it when you don’t want it any more.
If you elect to use "anti-virus" software, familiarize yourself with its limitations and potential to cause adverse effects, and apply the principle immediately preceding this one.
Most such utilities will only slow down and destabilize your Mac while they look for viruses that do not exist, conveying no benefit whatsoever - other than to make you "feel good" about security, when you should actually be exercising sound judgment, derived from accurate knowledge, based on verifiable facts.
Do install updates from Apple as they become available. No one knows more about Macs and how to protect them than the company that builds them.
Summary: Use common sense and caution when you use your Mac, just like you would in any social context. There is no product, utility, or magic talisman that can protect you from all the evils of mankind.

HAVE NEW 13.3 MAC AIR AND when using it to open sites in safari I have no issue until I go to a link page that is a pdf file or I am trying to save the screen info as a pdf. I only get a black screen with no data, cannot find solution in help menu

HAVE NEW 13.3 MAC AIR (previously, still have 13.3 MCbook pro which works captures what I am looking for an answer to)
when i open sites in safari the page opens fine if it is not a pdf based page.
Once i open a site that has a link to another page that is a pdf based page the page comes up as a black screen with no info showing
If I open a site that gices me an open to save a file to a word, excel type document or a pdf , everything works fine until I try to save the information to a PDF and again the screen goes black
I have tried the safari help site but to no avail, does anyone have a solution to thid problem. (I do have the abode ofr mac program loaded)

If you delete all the Adobe Reader stuff it will probably fix this. For almost everything, the Apple pdf handling works better.

HT202157 HOW CAN I WATCH MY MAC AIR IN MY APPLE TV

Hi someone can help I want to watch my browser for my mac air to my tv. Can I use my apple tv (3rd)?

Welcome to the Apple Community.
AirPlay Mirroring requires a second-generation Apple TV or later, OS X 10.8 or better and is supported on the following Mac models: iMac (Mid 2011 or newer), Mac mini (Mid 2011 or newer), MacBook Air (Mid 2011 or newer), and MacBook Pro (Early 2011 or newer).

Can anyone help me, I work on my mac air most days and would like certain folders to automatically update onto my iMac when i return home, is there a way of doing this? Many thanks.

Is there a simple way of linking the same excel folder on my imac and mac air, so as the one on my imac would automacily update when i return home, from the mac air? Fairly new to all this, so any help would be appreciated.

Open a Finder window and you should have a folder called iClouDrive in your home folder. Drag your documents or folders you want to share into this folder and it will be available on your other computer (look in the same folder).
As already mentioned Dropbox is a good solution; however, I like to use my free 5 GB from Apple's iCloud because I am not using very much space there. I reserve my Dropbox for other uses such as family photo and recipe sharing.
Good luck!

Mac air virus

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