Left 4 Dead 2 doesn't work on my PC anymore?? Help!

So I play Left 4 Dead 2 quite often. However, recently I have had a hard time with it. I start it up, and immediately I see a black screen and hear that error message sound. But I can't see what the error is because I'm stuck in black screen! The other day I let it go for 15 minutes to see if anything would happen. It was still at black screen. I have tried uninstalling and reinstalling it, but that doesn't work. What the hell do I do?

bump

Uninstall, and make sure you actually go around your system and manually delete any files that get left behind in the uninstallation. There might be stuff in "My documents", and some left over stuff in the game's steam directory, as well. Then reinstall. If it still doesn't work, have steam verify the game cache integrity. If steam says it's all good, and it's still not working... The problem is likely with your system.

Alright thanks.

Skyrim and Planetside 2 are running just fine so idk wtf this is. 

Verify cache, update drivers if you haven't.mep69