As you probably know, GameSpy shut down its services in 2013, which emptied the in-game server browser.
swat4stats.com now provides its own master server alternative for players to browse servers in-game and for server owners to list their servers.
To use the new master server, install this master server patch in just two clicks
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P.S. This would not be possible without the valuable insights and research performed by BaDTimE, the true hero of the SWAT 4 community.