Arma 2 Operation Arrowhead Steam Error Help

Ok this has never happened to me before, so I&downloading arma 2 Combined operations from steam. This includeds arma 2 and arma 2 operation arrowhead. (Its a package deal) Anyways I can play arma 2 fine but when i go to load up arma 2 OA (Operation Arrowhead) I get this error message. binconfig.bin/CfgInGameUI/MP.table.shadow I hit ok then the game crashes and another error comes up, Error compiling pixel shader PSSpectacularAlpha:0 idk what to do mabe you can help me? I&tryed Re-installing x3 Run as admin. x2 verify game cashe x2 Running with out steam + Admin x1