Dawn of War II Co-Op Crashing

[Furnished Coin]

-I have beaten the singleplayer campaign for the vanilla game and Chaos Rising on ultra settings (except for certain missions when it would crash at a certain point only)

- I am running Windows 7 64 bit and using a GTX 580 \

-I have updated everything suggested (video card, steam, etc.)

*My problem is that when I try to play a co-op campaign with my friends, my game freezes and forces me to ctrl alt del out with either NO error message, or with the dump file 183 message which I never get except when this occurs in Co-op

I have tried to turn my graphics down through the entire available spectrum, ran as administrator, and verified game cache/defrag game files (I have the steam edition)

Help would be appreciated,

Thanks

[Pulse.r]

What happens if your friend hosts the co-op session? Have you checked Windows Update for any GFWL updates?

[Furnished Coin]

My GFWL is fine, I alsso play Super Street Fighter IV for PC with no issue, and that requires live to play aas well, I have it updated. I'll try to see what happens if my friend hosts a session though