I'm currently dual booting Lion/Win7. I purchased and downloaded Mountain Lion from the Mac store, but when I went to upgrade, both disks were grayed out. When I click on either disk I get the following error message "This disk doesn't use the GUID Partition Table scheme." I went to disk utilities and sure enough my hard drive's partition map scheme is master boot record (not sure why). I do not have an external hard drive and do not want to lose any data. I did some research and apparently theres a way to patch some files to allow installation on a MBR partition scheme, however this is for Hackintosh users
I've tried modifying the tutorials myself to see if i could get it working
I have wasted 20$ on MLion and 22 hours of time trying to figure out a solution. help anyone? please don't tell me I'm SOL
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Install Mountain Lion from MBR Partition Scheme
- Thread starter Freezetd
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Repair your OS x partition. Follow the steps in the Apple document Resolve startup issues and perform disk maintenance with Disk Utility and fsck. Follow the fsck steps and run the fsck -fy. Keep running the fsck-fy until it says all is good, then type the reboot to boot back into OS X.
Then try to install 10.8 and see if that works.
Then try to install 10.8 and see if that works.
