Does a reinstall on mountain lion erase all data?

Hi, i just found out that there's a thing called OS X Recovery that lets you reinstall OS X, and as I recently upgraded from SL to ML, i wanted to know if a reinstallation would reset my mac as SL or ML, and also if this reinstallation would erase all of my data (because that's want i really want), so that then i could put my old data back from a time machine backup (if it is feasible to do so, as the time machine backup contains a backup from when i had SL) Thanks!

It will re-download and re-install from the Internet:
OS X: About OS X Recovery

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Will buying mountain lion erase all my data?

I am quite interested in updating to Mountain Lion, as I have a very outdated Mac. However, I am worried that doing so will erase all my data. Also, will updating make my mac run faster? It has been working much slower recently. Its only three years old, 10.6.8. Please help!

In addition to BT's comments:
The OS X update process will stomp on your /Applications, but not on the content in /Users, which is where your login directory resides. Good backup habits are sound advice.
Even if your three-year old Mac complies with the minimum supported hardware specs, it is very unlikely that a larger, more resource hungry Mountain Lion will give you more features and run faster on your hardware.
If you wish to stay current with OS X releases, at some point, you will need to step up to a new or refurbished hardware purchase decision.

Will Reinstalling Mountain Lion Erase My data ?

Please Help,
I am haivng issues with FACETIME and MESSAGES, both are not letting me log in. I have tried several accounts but no luck.
I tried Keychain Unknown Certificate deletion as well, still no luck. I still cannot log in to both.
Now i believe only solution is Reinstalling Mountain Lion.
My questions :-
1) Will it re download the entire setup of moutain lion from server ??
2) Will it Delete my Data ??
3) Will it resolve my certification issue and FIX my "Messages" and "Facetime" ??
Please help me asap.
Thanks in Advance.

Boot up holding command-r keys into your Recovery Volume.
The screen should give you these choices...
Restore from TM backup
Reinstall Mac OS X
Get help online
Disk Utility
First run Disk Utility Repair Disk, if you get errors run until no errors reported or reports "the disk cannot be fixed". Then, choose Reinstall OS X. This will be an install "in place" and shouldn't effect any of your own data or settings.

Why does the OS X Mountain Lion Up-to-Date Program email didn't arrived?

I ordered Mountain Lion yesterday!

Server perhaps overloaded?
I say give it until the weekend for the code and if not, call into Apple.

Reinstalling Ox Mountain Lion

If I reinstall Ox mountain lion will it erase all my data on that partion

Depends on how you reinstall. You can reinstall over the existing system or you can erase and install. The latter will remove everything on the volume. The former only affects the system files being replaced.
Reinstalling Mavericks, Lion/Mountain Lion Without Erasing the Drive
Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
Repair the Hard Drive and Permissions: Upon startup select Disk Utility from the main menu. Repair the Hard Drive and Permissions as follows.
When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu.
Reinstall Lion/Mountain Lion, Mavericks: Select Reinstall Lion/Mountain Lion, Mavericks and click on the Continue button.
Note: You will need an active Internet connection. I suggest using Ethernet if possible because it is three times faster than wireless.
Install or Reinstall Mavericks, Lion/Mountain Lion from Scratch
Be sure you backup your files to an external drive or second internal drive because the following procedure will remove everything from the hard drive.
Boot to the Recovery HD:
Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
Erase the hard drive:
1. Select Disk Utility from the main menu and click on the Continue button.
2. After DU loads select your startup volume (usually Macintosh HD) from the
      left side list. Click on the Erase tab in the DU main window.
3. Set the format type to Mac OS Extended (Journaled.) Optionally, click on
        the Security button and set the Zero Data option to one-pass. Click on
      the Erase button and wait until the process has completed.
4. Quit DU and return to the main menu.
Reinstall Lion/Mountain Lion, Mavericks: Select Reinstall Lion/Mountain Lion, Mavericks and click on the Install button.
Note: You will need an active Internet connection. I suggest using Ethernet if possible
            because it is three times faster than wireless.

HT2357 So how does this work on Mountain Lion? I cannot seem to ignore the iTunes 11 updates, which now seem to appear every 5 minutes!!

So how does this work on Mountain Lion? I cannot seem to ignore the iTunes 11 updates, which now seem to appear every 5 minutes!!

Fantastic! Didn't work at first so restarted App store and tried again. This time it asked 'ignore update'. All gone!

Upgrade from Snow Leopard to Mountain Lion erase my Windows partition?

Dear all,
I know some one might have asked it but I just wanna re-confirm.
Would the upgrade from Snow Leopard to Mountain Lion erase my Windows partition? I am currently using Bootcamp on my Macbook Pro (Late 2010 Version) and I do not have parallel desktop. I asked the same question when Lion was released, but HK Apple Store said YES and Melbourne Apple Store said no. I am a bit confused now.
Thank you for answering. Cheers!

Nothing.
That said, you should ALWAYS have a backup as anything can happen at anytime.

Time Machine backup from clean reinstall of mountain lion

I have a few niggles before and after installing mountain lion. Previously using snow leopard.
I want to do a clean reinstall of mountain lion and then use time machine to restore files and folders.
I dont want to do a full restore of time machine as i dont want to restore my niggles.
When I currently go into Time machine the restore button is alwats greyed out.
I am therefore not confident of being able to restore files selectively after clean reinstall.
I must admit I dont fully understand how time machine works after reading various tips and instructions.
Can anyone help or steer me in the right direction please.
Niggles include:-
Cant run Kaspersky or Sophos
Shutdown and restart problems
Small Desktop screen in front of blue screen after leaving idle for a while
Thanks

macfan110 wrote:
When I currently go into Time machine the restore button is alwats greyed out.
That button should be enabled once you navigate to a backup and select something.
But it's not going to work that way once you erase the internal HD. That's because the erased drive is treated as being a different one. Since the "old" drive isn't connected, you can't restore things to the place they were saved from, via the Restore button.
But you should be able to select what you want, right-click it, and choose the Restore <item> to ... option, to get a prompt to select the "new" drive.
Also, if you don't use either Setup Assistant or Migration Assistant to put your stuff back, Time Machine will do a full backup of the "new" drive. You may be able to prevent that, by telling it to "associate" the "new" drive with the old backups, per #B6 in Time Machine - Troubleshooting

HT1338 preview does not work with mountain lion

I updated my mid 2011 mac mini to mountian lion and i find Preview and all of MS Office 2011 for MAC fails to work
I can cut and paset the logs, but lets astart with assessing whagt does not work with Mountain Lion.

Your profile lists a 2008 MacBook with Snow Leopard.
I installed Windows XP into Bootcamp on my 2009 MacBook Pro (either in Leopard or Snow Leopard, I do not remember which) and I used it with Parallels 6.
When I upgraded it to Lion, even though the Lion Bootcamp will NOT install Windows XP, my Bootcamp (and use by Parallels 7) survived the upgrade.
It may be possible that it will also survive and operate a future upgrade to Mountain Lion.

Hi! is it possible that Logic X has upgrades that work only with mavericks and does t work in mountain lion....since in my macbook pro with mavericks i have new views of the equalizer, etc and in my mac pro with mountain lion it still the old view...

Hi! is it possible that Logic X has upgrades that work only with mavericks and does t work in mountain lion....since in my macbook pro with mavericks i have new views of the equalizer, etc and in my mac pro with mountain lion it still the old view...

Any OS version of 10.8.4 or later has all features that are not OS depended. The plugins are one example. You probably haven't updated all versions of Logic Pro X to the latest one.

Does the OS X Mountain Lion upgrade include iPhones and iPads?

This is probably a dumb question, but does the OS X Mountain Lion upgrade automatically include iPhones and iPads?

I don't know quite what you mean. Mountain Lion is for Macs and has nothing directly to do with iPhones and iPads at all.

HT2474 I did a clean reinstall of mountain lion and for some reason the dock keeps osx lion format

I did a clean reinstall of mountain lion and for some reason the dock keeps osx lion format. Does someone how to uptade only dock application?
Tks

Try doing a Dock restart using the following Terminal command:
killall Dock
Log out/in and test. If that doesn't work.
You need to look in your user Library/Applications Support/Dock for the .db. Hold down the option key while using the Finder “Go To Folder” command. Enter ~/ Library/Applications Support/Dock. Move the .db to your desktop.
If you prefer to make your user library permanently visible, use the Terminal command found below.
http://osxdaily.com/2011/07/04/show-library-directory-in-mac-os-x-lion/
You might want to bookmark the command. I had to use it again after I installed 10.8.4. I have also been informed that if you drag the user library to Finder it will remain visible.
Then try a dock reset.
Applications/Utilities/Terminal enter the command
killall Dock
Log out/in test. If it works okay, delete the .db from the desktop.
If the Dock is the same, return the .db to where you got them from, overwriting the newer ones.

Tried to reinstall OSX Mountain Lion 10.8.4 and every time i start with the installation i get a requested time out message, had to shut down my MacBook Pro retina. Now when i start up it automatically start internet recovery

tried to reinstall OSX Mountain Lion 10.8.4 and every time i start with the installation i get a requested time out message, had to shut down my MacBook Pro retina. Now when i start up it automatically start internet recovery for two ouers. After the internet recovery the same problem with reinstalling OSX message

Gave up on the GUI. This script derived from http://blog.netnerds.net/2012/07/os-x-how-to-setup-nat-on-lion-and-mountain-lion / seems to work for me:
gwdev=en0 # This is my WiFi connection (has Internet connection)
targetdev=en1 # This is the USB to Ethernet adapter (to give Internet connection)
/sbin/ifconfig $targetdev down
/sbin/ifconfig bridge0 create
/sbin/ifconfig bridge0 up
/sbin/ifconfig bridge0 addm $gwdev
/sbin/ifconfig bridge0 $HOST_ADDR
/sbin/route add default -interface bridge0 -ifscope bridge0 -cloning
/usr/sbin/sysctl -w net.inet.ip.forwarding=1
/sbin/ipfw add 100 divert natd ip from any to any via $gwdev
/usr/sbin/natd -interface $gwdev -use_sockets -same_ports -unregistered_only -dynamic -clamp_mss -enable_natportmap -natportmap_interface $targetdev

How to erase all data on macbook pro and reinstall operating system

how to erase all data on macbook pro and reinstall operating system

OS X Snow Leopard
https://support.apple.com/en-us/HT3910
http://www.thesafemac.com/how-to-reinstall-mac-os-x-from-scratch/
OS X Yosemite
https://support.apple.com/kb/PH18869?locale=en_US&viewlocale=en_US
Best.

How do you install mountain lion on all your macs in the household using one 20 dollar license?

how do you install mountain lion on all your macs in the houshold with the same license (you only pay 20 bucks for all your macs) is that right?

As long as they're all logged into the Mac App store with the same Apple ID, you can re-download the installer to all the Macs.
Or you can save a copy of the installer file before you run it and use that to update the other Macs. The ML installer file will appear in your Applications folder when it's done downloading. Copy it to another location (don't move it).
If you don't copy it before you upgrade, it will disappear when ML is finished installing.

Does a reinstall on mountain lion erase all data?

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