I've found that GPU drivers pulled down from windows update for AMD cards to be particularly problematic. If that's where you got them, there's a good chance that's your problem. It's rare that I've had trouble with official AMD releases though. I know people that would curse me for that statement! What's specific buttons do you use to exit? Anyway that is possibly conflicting with something else you recently installed? Is this when exiting a MAME game, console emulator, Daphne, or just exiting anything in general? If it's crashing only when exiting MAME, does it behave the same way in GameEX Lite? Just some ideas, and it couldn't hurt to run system file checker. from an elevated command prompt: sfc/scannow Have you recently installed new codecs?