I have the correct software, I have backed it up, and I am up to date software wise. I've downloaded Mountain Lion and am installing but it won't let me choose Macintosh HD, it says 'This disk is used for Time Machine backups'.
I'm getting annoyed now.
Partion failed with the error:
Could not modify partition map because filesystem verification failed.
Any ideas why?
Foodage wrote:. . . 'This disk is used for Time Machine backups'.
. . .
'This disk is used for Time Machine backups'.
Somehow, a Backups.backupdb folder got created on your startup drive.
You won't find it via a Spotlight or Finder search, so open your internal HD via the Finder.
That folder is at the top level. Just delete it.
Retrieving data ...