Starting Killing Floor crashes Steam

[notsol337]

When I run Killing Floor, my Steam client crashes. Once Steam crashes, Killing Floor follows it into crash land and the only error messages I get are "Steam <number> has stopped working" and "Killing Floor is no longer responding."

I'm running Win7 64 bit with the newest drivers/direct x (I just updated them to see if that would fix it.) I'm using an nVidia 8800gts, and I've got 4 gigs of ddr2. The real kicker to this is that the game worked more or less flawlessly up until today, and I can't seem to find anyone else having a similar problem!

I've also deleted the game and reinstalled it to no avail.

Any ideas?