Why doesn't my iMac boot up? It only keeps re-booting, then shuts down and re-boots

For some reason, since installing Mountain Lion, I have had a lot of problems with the iMac starting...it keeps re-booting and re-booting...
what can I do to get into my iMac?

Srartup disk Full can destroy your Hard Drive installation.
Could be many things, we should start with this...
"Try Disk Utility
1. Insert the Mac OS X Install disc, then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu at top of the screen. (In Mac OS X 10.4 or later, you must select your language first.)
*Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.*
3. Click the First Aid tab.
4. Select your Mac OS X volume.
5. Click Repair Disk, (not Repair Permissions). Disk Utility checks and repairs the disk."
http://docs.info.apple.com/article.html?artnum=106214
Then try a Safe Boot, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, reboot when it completes.
(Safe boot may stay on the gray radian for a long time, let it go, it's trying to repair the Hard Drive.)
If perchance you can't find your install Disc, or are running 10.7+, at least try it from the Safe Boot part onward.
If 10.7.0 or later...
Bootup holding CMD+r, or the Option/alt key to boot from the Restore partitiion & use Disk Utility from there.
If it starts in Safe Mode, see if you can empty the trash or free up a few GB by trashing files.

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Why does my ipod sometimes flashes white then shuts down and then the only way to restart is to restore?

why does my ipod sometimes flashes white then shuts down and then the only way to restart is to restore?

If you restored to factory settings/new iPod and still have the problem that indicates a hardware problem.
Make an appointment at the Genius Bar of an Apple store..
Apple Retail Store - Genius Bar

I'm on my iPod touch 4th generation and I wanna delete apps. Well I hold it down nd the X appears but as soon as I press the X it doesn't do anything for a little bit and then shuts down and turns on again by itself, HELP ME DELETE!

I'm on my iPod touch 4th generation and I wanna delete apps. Well I hold it down nd the X appears but as soon as I press the X it doesn't do anything for a little bit and then shuts down and turns on again by itself, HELP ME DELETE!

Try:
- Reset the iOS device. Nothing will be lost
Reset iOS device: Hold down the On/Off button and the Home button at the same time for at
least ten seconds, until the Apple logo appears.
- Reset all settings
Go to Settings > General > Reset and tap Reset All Settings.
All your preferences and settings are reset. Information (such as contacts and calendars) and media (such as songs and videos) aren’t affected.
- Restore from backup. See:
iOS: How to back up
- Restore to factory settings/new iOS device.
If still problem, make an appointment at the Genius Bar of an Apple store since it appears you have a hardware problem.
Apple Retail Store - Genius Bar

When I turn my iMac on, it appears to start up but then shuts down

Why does my iMac keep shutting down? I turn it on, the grey screen and apple logo appear, but then it shuts down...

Have you read for possible solutions over in the "More Like This" thread over here?----------------------->

After 3.1 update my iphone 3G shut down and wont boot up again!

I have used my iphone 3G on 3.1 software update for 2 days and it just shut down!
There's no apple boot logo when I try to start it again and it doesn't even respond to a single thing I do.
What do I do?
Has someone experienced the same issue?

You aren't the only one...
http://reviews.cnet.com/8301-19512_7-10357176-233.html?tag=TOCmoreStories.0
Try this first:
•Reset your iPhone by holding down the sleep and home buttons until the Apple logo appears.
Then go whine like the rest of us until they fix it here: http://www.apple.com/feedback/iphone.html

My imac 5.1 freezes or coloured spinning wheel then shuts down.

Hi
My imac 5.i freezes or has a spinning coloured wheel and locks up, or the screen goes white or shuts down on it's own .
Any help !

Hello:
Try resetting the PRAM and SMC.
If it continues, take it in for service.
Barry

HELP -- G5 Mysteriously shutting down and re-booting ???

Hello there.
I have a brand new G5 running the latest version of Tiger. This system does something very strange.
While running with the screensaver on - or just while running with the screen sleeping this new G5 reboots itself after about one to one and one half hours.
I have had iTunes running on this new G5 while I work in my office, after about an hour the iTunes stops, and when I hit a key or move the mouse to wake the G5 back up - the machine has shut down all applications, and wants me to re-login (username and password) as if I had just booted it up! This has happened ever since I purchased this unit a couple weeks ago.
The machine does this while running peer-to-peer software, iTunes, etc - it shuts down the monitor - continues to run the app, then (after about 1 to 1.5 hours) it is apparently reboots itself, after shutting down the applications?
I have owned many Macs - have been running Tiger on a G4 and it never has occurred except on this new machine. Is this machine possessed by Satan, or is this some kind of new Apple trick?
Any constructive feedback would be most appreciated.
Thanks!

Well. seems that a system preference might be turned on.
Go to system preferences> Energy Saver> (under sleep) Click on Schedule, make sure all of those options are turned off... if any are, then there is your problem, just uncheck them.
If not..
Go to system preferences> Security: See if the checkbox for "Log me out ** minutes of inactivy" is checked, uncheck if it is.
if not, look for the "require password to wake from sleep or screen saver" checkbox...
I hope one of these solves it...
Dont forget to leave rep points.
patrick

I am trying to download and install Firefox 4. 0. 1. The download works, but what I am supposed to do to install it? If I shut down and re-boot I am prompted each time to download the same update. Thanks - PM

Firefox prompts me that I need to download and install an update. This I do, and it downloads, but I don't know how to install it. This might be happening automatically, but when I shut down and re-start, I get the same message about installing the same update. Unless I can resolve this, I will have to return to Internet Explorer... What can I do?

Do a clean (re)install and delete the Firefox program folder (C:\Program Files\Mozilla Firefox\).
If there are problems with updating then best is to download the full version and uninstall the currently installed version and delete the Firefox program folder to remove any leftover files.
Download a fresh Firefox copy and save the file to the desktop and close Firefox.
*Firefox 10.0.x: http://www.mozilla.org/en-US/firefox/all.html
Uninstall your current Firefox version, if possible.
*Do NOT remove personal data when you uninstall the current version or you lose your bookmarks and other data because all profile folders will be removed.
Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.
*It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.
*http://kb.mozillazine.org/Uninstalling_Firefox
Your bookmarks and other profile data are stored elsewhere in the Firefox Profile Folder and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.
*http://kb.mozillazine.org/Profile_folder_-_Firefox
*http://kb.mozillazine.org/Profile_backup
*http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall

I recently bought the first generation ipod touch, but it doesn't work. I've tried restarting over and over, i've tried switching cables too. The apple logo stays on the screen and freezes, it then shuts down and repeats. My laptop doesnt recognize it.

Please help
I bought it through a mutual friend.

- Connect the iPod to your computer and try to make a backup
iOS: How to back up and restore your content
- Next reset the iOS device. Nothing will be lost
Reset iOS device: Hold down the On/Off button and the Home button at the same time for at
least ten seconds, until the Apple logo appears.
and try making a backup again. If you can't then there is no way of getting the info off the iPod unless data recovery company can do it. Not cheap.
- If photos are in an existing iPod backup (iTune>Preferences>Devices for iTunes backup or an iCloud backu) then restore from that backup. See the restore topic of:
iOS: How to back up
- If you used PhotoStream then try getting them from your PhotoStream. See that topic of:
iOS: Importing personal photos and videos from iOS devices to your computer

Why doesn't my iMac tell me what is being down loaded when I can see that my modem is downloading something

why doesn't my imac tell me what is being dowloaded when i can see that my modem is downloading something?

There are many reasons for the activity light on your cable or DSL modem to be flashing. Your Mac could be checking for or downloading updates in the background. It could be checking e-mail. It could be syncing a cloud service like iCloud, Dropbox, etc.
If your Mac isn't the only thing on the network, then the light could be flashing due to some other device on the network downloading an update, syncing something, etc.
And, of course, it's always possible your network is under attack by an automated botnet or something. You'd be surprised how often a device exposed to the internet directly - as a modem like this is - will be hit with attempted attacks, in an attempt to find things that are vulnerable.

Why doesn't my iMac G5 accept my password?

Why doesn't my iMac G5 accept my password?

When you are doing what?
BTW, what version of OS X are you running?

Why doesn't my imac turn on when I turn on Apple TV?

Why doesn’t my imac turn on when I turn on Apple TV?

Yes, otherwise some people might have to walk up to the third floor and turn on iMac,
and then go back down to living room in order to stream form iTunes. My iMac is close,
but not in same room. There must be something I don't have set up right.

Since installing OSX 10 my iMac randomly shuts down and restarts. I can not determine why this is happening. Any ideas?

Since installing OSX 10, my iMac randomly shuts down and restarts. I can not determine why this is happening. Any ideas?

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.

Why doesn't my iPhone connect to tv? Keeps saying "this accessory is not supported by this iphone"

Why doesn't my iPhone connect to tv? Keeps saying "this accessory is not supported by this iphone"

I assume you are running ios 8.x. It's a bug.
Wait for a fix from apple. ... OR ... You could buy a new Apple brand connector. The latest connectors will work, even the older apple brand connectors do not work. OR try re-booting your ipad. OR wait until the video starts then attach the connector.
more info here:
Re: 30 pin to VGA adapter won't work since iOS 8
unable to use HDMI adapter after iOS 8.0 upgrade

Why doesn't apple have a file of events that ties to the iCal program and the Address book file? By having that relationship it seems that you could call up all of the events tied to a customer while in the address book or likewise call up all of the even

Why doesn't apple have a file of events that ties to the iCal program and the Address book file? By having that relationship it seems that you could call up all of the events tied to a customer while in the address book or likewise call up all of the events tied to a contact that was in the iCal program as a scheduled meeting. Even in the to do's you could easily look back at the events tied to an individual so as to bring yourself up to speed with what you were doing with the individual in mind.

I definitely understand your concern and I apologize for all the frustration. Verizon Wireless has a strong customer commitment to delivering the best from our service and staff. I am disappointed to hear the service you received did not reflect this commitment.
I definitely want to help get to the bottom of this and further assist you. Please reply to my direct message so I can access your account and further assist. I am sure we can get this resolved.
JohnB_VZW
Follow us on Twitter @VZWSupport

Why doesn't my iMac boot up? It only keeps re-booting, then shuts down and re-boots

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