Well let see where to start? I have both Arma 2 & Arma 2 - OA from Steam, when I updated to the lastest version thru steam I can only run Arma 2? I have tried everything in this forum's Post, and nothing seems to work... I have tried uninstalling Arma 2 - OA and then re-installed it then revalidated Arma 2 before trying to run OA or Combined Ops. I have also DL'd the "_runA2CO.cmd" file also and Nothing is working for me... I have "Windows 7 Ultimate x64", everything ran fine before this damn update... and to be honest, this is getting extremely annoying to go thru after every update!!! Any help would be Greatly Appreciated!