13 Replies Latest reply: Dec 16, 2012 8:26 AM by architextus
Blewyn Level 1 (25 points)

I have a Win7 partition on my Macbook with the latest Snow Leopard OSX. If I upgrade to Mountain Lion, will it preserve the Win7 partition and leave it bootable, or do I have to reinstall the whole thing?

MacBook Pro, Windows 7
  • JoBoxxx Level 2 (170 points)

    It should not affect your bootcamp partition.

  • Ryan M. Level 6 (8,180 points)

    Since Mountain Lion is just an upgrade, it will preserve all data.  I'd recommend backing up regardless as it's always a good idea.

  • mende1 Level 10 (92,156 points)

    The installer only upgrades your system to 10.8, Boot Camp isn't affected, but you can download the latest drivers in Assistant

  • Allan Eckert Level 9 (50,689 points)

    I suspect that the upgrade if it works correctly should not impact your Win 7 partition but to be sure you really should post your question over in the BootCamp forum where the Windows guru hang out.



  • RAH97 Level 1 (0 points)

    FWIW, I upgraded to Mountain Lion this morning and Boot Camp stopped loading my Windows 7 install.  The partition is still there, but when I select it as my startup drive I get nothing but a black screen.

  • Donn Lewis Level 1 (0 points)

    I have Win 7 in bootcamp and installed Mountain Lion.  My Win 7 partition was fine, and I successfully booted into Windows.  No issues.

  • thatoneappleguy Level 1 (0 points)

    Did you select your starup disk from within OS X? I can reboot from within OS X to Windows 7 but if I choose the starup disk during boot it hangs after the selection. Anyone else having a similar problem?

  • Splinter Head Level 1 (0 points)

    I'm having the same problem. I upgraded to Mountain Lion yesterday and went to boot Windows using the option key, and then again by changing the startup disk. Option key did not even list Windows and the startup disk said that no bootable code was on this partition. Do I need to start Windows Boot Camp again (luckily there wasn't much on it) or is there a fix out there?

  • Nickolino Level 1 (0 points)

    I have the same problem as Splinter Head. I can't find my Windows parition to boot from after I installed Mountain Lion.

    Will it work if I use time machine and go back to Lion?

  • Blewyn Level 1 (25 points)

    FYI thread followers, I installed ML and my MBPro continues to boot to Win7 by default or OSX/WIn7 by option key screen - no problems whatsoever.


    My mac was set to boot to Win7 by default before I ran the upgrade to ML.

  • taylor136 Level 1 (0 points)

    Ah same here as you guys, I had mine set up to boot win automatically and after installing ML I can't even get the dual boot screen to show up at all. I made a new thread about it,




  • architextus Level 1 (0 points)

    I have Snow Leopand v10.6.8 and BootCamp v.3.0.4 installed on my iMac i7. I run Windows 7 on BootCamp and want to upgrade to Mountain Lion.


    I downloaded Mountain Lion, but haven't installed because I'm concerned about BootCamp compatibility. roaringapps.com indicates BootCamp 4.0 has not been tested with Mountain Lion. I backed up the Mac HDD to Time Machine.


    I tried to update the BootCamp software to v.4 for the Mountain Lion upgrade, but Software Update says my software is up-to-date. I I tried to download Windows support software (to update BootCamp), but the Boot Camp Assistant says "The Windows support software is not available."


    My computer is set to boot Snow Leopard and I switch to Windows (BootCamp) when I need it.


    When I check the Bootcamp version from the Windows 7 side, it shows v3.3.


    My question is:


    For those of you who successfully upgraded to Mountain Lion from Snow Leopard, what version of BootCamp do you have on Snow Leopard?


    Did you have to upgrade BootCamp after you installed Mountain Lion? Did it work?

  • architextus Level 1 (0 points)