i'm having a bit of an odd problem that i haven't seen mentioned yet. i was fine installing under XP Compat, and even had the game running. i went to update Windows Live from within game when it asked me (which i found out later was not recommended). the update file couldn't access the exe because it said it was being used, even though it wasn't, so i had to cancel the update half way through. the game stopped working so i uninstalled and when i installed everything again...
social club launches, but as soon as i try to launch GTA4, the windows progress wheel starts spinning and then stops and it does nothing. no error or anything.
this is so frusterating. i've tried running it in every compat mode. nothing works.