My guess is that when you try to join a multiplayer server, the game looks for a entry in HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\LucasArts\Star Wars Battlefront II\1.0 (this seems to be the registry entry for the retail version) Since GOG doesn't provide a cd key, the installer did not create a registry entry for it. If you have a 64-bit version of Windows, go to : HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ If you have a 32-bit version of Windows, go to : HKEY_LOCAL_MACHINE\SOFTWARE\ Be careful when manipulating the registry ! Do not delete anything and stick to the instructions below.Ģ. Right-click regedit.exe and select 'Execute as administrator'. Open the windows start menu and type 'regedit'. For the retail version, CD keys are located in the windows registry.ġ.
So all you have to do is provide the game with one.
The game seems to be looking for a key when joining a multiplayer server, and since it doesn't find one, prevents you from joining the game. I found a workaround if you purchased the game elsewhere and actually have a CD key.