Crashes when opening Multiplayer session

Hi, I have had GMod for a while now and it has been working perfectly until a couple of days ago, Whenever I try and open a multiplayer session(Hosted Locally or server), it will try to connect and half way through, GMod will crash saying “hl2.exe has stopped working”. I have tried known fixes like -dxlevel 80 and that doesn’t work. I don’t know what to do about this because it has always worked until now.
I would greatly appreciate some help with this,

[editline]9th September 2012[/editline]

Never mind, I fixed it.

(User was banned for this post ("wrong section, didn't bother looking around" - postal))