MacOS – Upgrading Snow Leopard to Mountain Lion and preserving Bootcamp partition

bootcampmacospartitionsnow leopardupgrade

I have a 2010 MacPro running SL with a bootcamp partition (on the same bootdrive) containing a Windows 7 x64 installation which I use for work. I was about to upgrade the Mac to Mountain Lion but I'm concerned that doing so will make the Windows 7 partition unbootable. If its an anavoidable side-effect of upgrading I will have to image the windows partition and restore it once I've done the upgrade, but with >500GB on the Windows side of things, I would rather not.

I can't seem to find a definitive answer on the web, can anyone confirm or deny my suspicions?

Best Answer

I have succesfully upgrade two machines without having any issues with the Bootcamp Partitions or the actual installation. The upgrade doesn't seem to the touch the actual partition scheme unless it is a HFS partition. I also did the upgrade on a Tripple Boot MacBook without any issues.

I have also done a clean installation of Lion onto a machine that had a bootcamp partition without issues, as long as you don't delete the partitions.

As always, make sure you have a backup of the important Windows portions as for safety, however go ahead with the upgrade, it should only affect your existing OSX partition.