Here’s a quick tip on moving Guitar Hero 3: Legends of rock to a different directory/disk drive
After moving you’re guitar hero 3 folder, Open regedit (start->run->’regedit’) and browse to the following folder:
HKEY_LOCAL_MACHINE/SOFTWARE/Aspyr/Guitar Hero III (32 bit)
HKEY_LOCAL_MACHINE/SOFTWARE/Wow6432Node/Aspyr/Guitar Hero III (64 bit)
Change the key labelled ‘Path’ to match your new directory. Then run GH3.exe, and all should work.