Season 1 of Call of Duty: Modern Warfare 3 has been a little rocky, with different errors plaguing players across multiple platforms. The latest is a multiplayer matchmaking update error saying, “Join failed because you are on a different version.” Here’s how to fix it.
Matchmaking Issues: How to Fix the Join Failed Different Version Error in Modern Warfare 3
In short, the Join Failed Different Version error is caused by the version of MW3 on your PC being different than those of the other players on the server. Right now, it appears the issue is confined to BatteNet users. While it’s unclear exactly why it happened, for some reason, the BNet version of Modern Warfare 3 was updated to the 10.4 version of the game before other platforms, including Steam, PlayStation, and Xbox.
As a result, there is no current fix to the “Join failed because you are on a different version” error. I don’t know if Call of Duty HQ can actually do version rollbacks. Though, in my more than 10 years of using the platform, I’ve never seen it happen. Sledgehammer Games and the Call of Duty support team are aware of the error, and announced such on their official social channels:
How to Check Your MW3 Version on PC
To check which MW3 version you have, log into Call of Duty HQ and look at the bottom right of your screen. In my case, as I have the game on Steam, my version is 10.3.167, plus a bunch of additional digits that don’t really matter.
If you’re a BattleNet user and your version starts with 10.4, you have the incorrectly updated version of MW3 and will be unable to play with your friends who aren’t on BattleNet. Patience right now is your only recourse, and hopefully, there are enough players on Blizzard’s platform to accommodate for the time being.
One final note: don’t log into Modern Warfare 3 on another platform using the account linked to BattleNet. Doing so will cause a separate conflict and likely reset your progression, much like the recent Niamey Logan error.
For now, there’s really not much else to do if you get hit with the Join Failed Because You are on a Different Version error. I wish there was more to do, but it looks like being patient and waiting for an official fix is about it. For more coverage of Modern Warfare 3, check out our guides on the best WSP Swarm build, how to use the Locked Diary in Zombies, and more in our MW3 guides hub.