I've just installed a new copy of CO, which includes my retail copy ArmA 2 and OA with steam. First I installed OA, I see it's patched to 1.60. After that I installed ArmA 2 on top of OA... this location: Steam\steamapps\common\arma 2 operation arrowhead Yes, I can see atleast that the maps are properly working when loading up CO. This is the error I get: Files "addons\a10.pbo", "addons\air.pbo", "addons\air2.pbo", "addons\air3.pbo", "addons\animals.pbo", "addons\animals2.pbo" ... are not signed by a key accepted on this server. To play on this server, remove listed files or install additional accepted keys. It's clean install, I only have dayz installed. (correctly I'm sure!) I get these errors ingame, when in the menu. No entry 'bin\config.bin/CfgVehicles/C130J/MFD/AirplaneHUD.Bones' and No entry 'bin\config.bin/CfgFontFamilies.zeppelin32mono'.