FIELD NOTES · Nov 6, 2026
Older Call of Duty games on PC: Plutonium, IW4x and AlterWare
Community clients add dedicated servers, server browsers and mod support to the PC versions of eight Call of Duty games. Which client goes with which game.
Why players use community clients
The PC versions of older Call of Duty games are still sold on Steam. Community clients run on top of your own copy of the game and add dedicated servers, a server browser, security fixes and mod support. They are not made by Activision.
Which client for which game
- Call of Duty: World at War: Plutonium
- Call of Duty: Black Ops: Plutonium
- Call of Duty: Black Ops II: Plutonium
- Call of Duty: Modern Warfare 3 (2011): Plutonium; AlterWare also has a client
- Call of Duty: Modern Warfare 2 (2009): IW4x; AlterWare also has a client
- Call of Duty: Ghosts: AlterWare
- Call of Duty: Advanced Warfare: AlterWare
- Call of Duty: Black Ops III: AlterWare
Plutonium
Plutonium covers World at War, Black Ops, Black Ops II and Modern Warfare 3. It adds a dedicated server browser, its own anti-cheat and modding support, and since 2023 it checks that players own the game. Its install documentation starts from a Steam installation of the game and asks for a forum account to log in to the launcher.
IW4x
IW4x is a multiplayer client for Modern Warfare 2 (2009). The original X Labs team shut its version down in May 2023 after a cease-and-desist letter from Activision; the current project is developed in the open on GitHub. Its documentation says it needs the latest Steam version of the game, that the Microsoft Store version is not compatible and that pirated copies are not supported. It is installed in the game's own folder.
AlterWare
AlterWare publishes separate clients: IW4-SP and IW5-Mod for Modern Warfare 2 and 3, IW6-Mod for Ghosts, S1-Mod for Advanced Warfare and T7x for Black Ops III. Its launcher downloads and updates the first four; T7x is a standalone client placed in the Black Ops III folder. AlterWare says it has patched exploits present in the Steam versions and is not affiliated with the rights holders.
Before you start
Buy the game on Steam if you do not own it, then download the client only from the project's own website. These clients are independent projects and can change or stop; check each website before installing.
Sources
- Plutonium
- Plutonium - install documentation
- IW4x documentation
- AlterWare
- PC Gamer - Activision shuts down the X Labs IW4x project (2023)
- GGRecon - Plutonium adds checks against pirated copies (2023)