I have 3 partitions, main with 10.8 (now updated to 10.9), Bootcamp with W7 and 10.6 for playing older games. My 2010 iMac came with 10.6. It all worked under 10.8, but after installing Maverick I can't boot into 10.6 (holding down ALT with startup) and when trying to boot into W7 I get a black screen that Windows needs it install DVD and need to perform a clean install, it can't fix it.
Furthermore, Windows can only be selected in system preferences, selecting startup disk, not when restarting holding the ALT button.
10.6 can only sometimes be selected at startup with ALT, it doesn't show in the startup disk. Have put a backup of this partition back through time machine, but it's still not recognized.
It seems both partitions with different OS's have been corrupted by installing Maverick. Has anyone else have this problem too?? Any help is appreciated!