hl2.exe crash

[Xn0o0cl3]

So my Valve games have stopped working :/. When I try to run one, it gets through the "preparing to launch" part, and just as they're about to play, hl2.exe crashes and it gives me the error report message. Half Life 2 seems to be an exception to this however, as it will make it to the main menu, then crash when I try to load/start a new game. It started happening a few days after I installed Zombie Master 1.1.3 (it started happening when I was playing that, the first few times it crashed in-game, then it would get to spectator view and crash, but now it won't even open the mod or other games.) But I deleted that and it still persists. Any ideas?

 

[Acepilotf14]

Delete Clientregistry.blob

 

[Xn0o0cl3]

I deleted clientregistry.blob and got nothing, so i unistalled all my valve games, then deleted any leftover local content, reinstalled everything, and it's still not working. Should I try uninstalling Steam, or is there something else I should do?