Just read my post above =\ It has a screenshot, which explains an issue perfectly. Stop running game client (MBII itself) BEFORE running a server. Start the server, THEN launch game (if you even need to run MBII, actually). OR, change port in game's config, NOT server's config: Jedi Academy\GameData\MBII\jampconfig.cfg Jedi Academy\GameData\MBII\openjk.cfg My Documents\My Games\OpenJK\MBII\openjk.cfg Game is not a server, but game opens port anyway. By default, that port is 29070. Port that is already opened cannot be used by any other process, including MBII server. Either shut down a process which took over 29070 (Movie Battles client), or make Movie Battles use some other port.