gamebooster...
ok every time i have game booster running... im on crossfire and i go on a 1 on 1 with a freind and every time i press start game or ready it zooms in and just freezes and i leave it for numerouse muinets and still no response so i came off game booster and walah i could join crossfire games but not with gamebooster running :@
Try not closing any processes while running it and seeing what happens.
Yeah, or run gamebooster THEN run crossfire.