7 Replies Latest reply: May 20, 2013 3:17 AM by Eustace Mendis
BlowYourMind Level 1 Level 1 (0 points)

Hi everyone,


I want to set my macbook pro (mid-2010) to factory settings, do a completely new, clean install. (Due to some issues with the boot-up speed etc)

But, my mac originally came with OS Snow Leopard.

I still want Mountain Lion to remain on my mac: How do I do this?

(So, just to be clear, I want a clean reinstallation of Mountain Lion (& erase all my apps and files that were on my mac))

MacBook Pro, OS X Mountain Lion (10.8.1)
  • macjack Level 9 Level 9 (50,650 points)


    First, have a good backup either Time Machine or SuperDuper or CCC clone.

    Use the DVD that shipped with your Mac to erase & install the original OS.

    Then upgrade to ML via the app store.

  • BlowYourMind Level 1 Level 1 (0 points)

    So I first have to erase my harddisk, and then reinstall from the cmd-r menu?

  • macjack Level 9 Level 9 (50,650 points)

    No, that was my mistake. That's only for Macs that shipped with Lion or ML. In your case you need to revert to Snow Leopard, then apply the ML upgrade.

  • BlowYourMind Level 1 Level 1 (0 points)

    Ok thanks. Will the ML upgrade be 'free' ? (Because I already payed for it)

  • Eustace Mendis Level 7 Level 7 (25,320 points)

    It's free. You will have to use the same Apple id for the previous purchase to be recognized.

  • jenifree Level 1 Level 1 (0 points)

    I have wiped my hard drive and am trying to reinstall Lion, but its just sitting there doing nothing.


    Any ideas?

  • Eustace Mendis Level 7 Level 7 (25,320 points)

    Internet Recovery should work:



    OS X Internet Recovery

    If you happen to encounter a situation in which you cannot start from the Recovery System, such as your hard drive stopped responding or you installed a new hard drive without OS X installed, new Mac models introduced after public availability of OS X Lion or OS X Mountain Lion, automatically use the OS X Internet Recovery feature if the Recovery System (Command-R method above) doesn't work. OS X Internet Recovery lets you start your Mac directly from Apple's Servers. The system runs a quick test of your memory and hard drive to ensure there are no hardware issues.

    OS X Internet Recovery presents a limited interface at first, with only the ability to select your preferred Wi-Fi network and, if needed, enter the WPA passphrase. Next, OS X Internet Recovery will download and start from a Recovery System image. From there, you are offered all the same utilities and functions described above.

    As with the Recovery System, reinstallation of OS X Lion or OS X Mountain Lion from OS X Internet Recovery requires an Internet connection. See "Supported network configurations and protocols" below.

    Some computers that did not ship with OS X Lion or OS X Mountain Lion installed may have a software update available that allows them to use Lion Internet Recovery.