Problems with starting games!

[User.]

I've just put together my new computer, works brilliant. I was playing source games last night fine, really happy with what I've got.

Though I woke up this morning and am getting this error:

I'm guessing it's a driver error.

I can load up server details fine, it's just when it's actually initialising the game it chucks me out into my desktop. Help would be really appreciated, thanks

 

[mikeymike]

try uninstalling DX9.0c then re-installing it?

 

[User.]

try uninstalling DX9.0c then re-installing it?

I've just uninstalled some of the more unnecessary drivers that I had initially. Although I think it's actually to do with the game itself. So I've just re-installed Steam client and am downloading the games now. See what happens from there.