After GameSpy shut down their master servers, Bohemia Interactive has integrated the Steam server browser into ArmA 2. The latest update which includes this change (version 1.63) is only available via Steam. CD Keys of retail copies of the game can be used to redeem the game on Steam and obtain the updates.
Note that the clients using the old version (1.62) will not be able to connect to any servers (including ours) on the new version (1.63).
To get that straight: if you have a non-steam version of the game, you can trash it. You MUST go to Steam, activate your key and download the game there. Ofc you have to reconfigure your PW6 as well.
