I beileve the issue is with the latest beta patch so that will not work. it will be fixed in the next patch but there are sevral work arounds. The bug is with the registry entry for player name . So some say create new windows account or reinstall sixlaunch/battleeye. I tested both, they do not work. What does work is if you go to regedit to following path HKEY_CURRENT_USER\Software\Bohemia Interactive Studio\ArmA 2 OA and create a new registry file, file is named: PLAYERNAME set the value to whatever you want your name to be. This is the way you can change your name in game on any windows named account.