# Animefan162a :
I get the errors "Addon 'MAP_EU' requires addon 'CASigns2'"
You seem to have more custom addons installed that you know of. I think this error means you are running just Operation Arrowhead and not Combined Operations (Arma 2 + Arma 2: Operation Arrowhead). However since you played DayZ you must have Arma 2 so check if you configured the launcher correctly to run CO.
and "No entry 'bin\config.bin/CfgSurfaceCharacters.CRGrassWClutter"
Again this seems to indicate you are not starting CO.
I still get the "Bad serial number given in setup" error.
Make sure to run both
the game in administrator mode (right click the shortcuts).