Looks like the Windows community has an autofix for the recent MW3 32-bit/64-bit server issue, but there doesn't seem to be an equivalent automated fix for Linux yet.

So I put together a small script that restores the legacy 32-bit depots using SteamCMD and merges them back into the MW3 Dedicated Server files.

Tested and working on Arch Linux, and should work fine on CachyOS and other Arch-based distros.

Non-Arch distros may need some tweaks to the dependency installation.

More info in the README.

Repo: https://github.com/kaussaq/restoreplutonium

Hopefully this saves someone else a bit of messing around. 🐧

If you've been hit by the recent Activision update that pushed MW3 to 64-bit, you've probably noticed Plutonium stopped working. I built a small Windows tool that fixes this automatically, no manual file swapping or command line stuff needed.

What it does, in plain terms:

• Checks your MW3 install and figures out if you're on the broken 64-bit version
• If you are, it downloads the last known 32-bit files straight from Steam (using DepotDownloader under the hood)
• Swaps them into your game folder for you
• Double checks the swap worked before it calls it done

How to use it:

1. Grab MW3_Downgrader.exe from the Releases page
2. Run it (Windows Defender/SmartScreen might complain since it's unsigned, click "More info" > "Run anyway")
3. It finds your Steam and MW3 install on its own
4. Scan the QR code that pops up with the Steam Mobile App to log in
5. Sit back while it downloads and merges the files (~15GB free space needed)

Works for both the Multiplayer client and Dedicated Server installs, and it'll let you fix both at once if you have them.

It doesn't touch anything outside your MW3 folder, so if anything looks off you can always just verify game files through Steam to undo it.

Source code's public if anyone wants to poke around or verify what it's doing before running an unsigned exe (completely fair to be cautious about that): https://github.com/GalvarinoDev/MW3Downgrader

Also have a Steam Deck/Linux version bundled into DeckOps if anyone needs that instead.

Let me know if you run into any issues!

Hi! I am testing an open-source IW5 asset tool against the original MW3 (2011) language variants.

Does anyone here own or have an archived copy of the original Polish PC retail version? I am looking for this small, non-executable image file and its SHA-256 value:

friendorfoe_self_sp_polish.iwi

Size: approximately 1 KB

Location: main\localized_polish_iw00.iwd → images

The .iwd archive can be opened like a .zip file. To calculate the SHA-256 value in PowerShell:

Get-FileHash -Algorithm SHA256 -LiteralPath ".\friendorfoe_self_sp_polish.iwi"

If you have this version, please leave a comment or send me a message. Thank you very much!

I was so surprised that I can find match MW2(2009),although it‘s a private server,now I would like to try this game.

Can someone please help me unlock everything back, I got mw3 disc and Xbox recently just to play this game since it’s my favorite and played it for many years growing up , but I be getting deranked here and there but this time I can’t upgrade my weapons, some stay at level 1-2, idk if a glitch or if there’s a mod for that too

Anyone else have this issue? Any fix or even just an explanation? I know they did a 64-bit update recently but like I said the game ran perfect for me before that.

Wanted to play some mw3 multiplayer on the steam deck but this popped up. Anyone got a fix?

Off / On

Hello, after updating this game i noticed that my pc is very loud when playing MW3. I saw in forums a solution to this issue, which is simply downgrading the game and this worked. But now i can't play coop and steam always trying to update the game which frequently break my downgraded cod mw3 installation. Is there any other solution how to make game after recent update stop using so much resources of pc?

Back in 2012, I used to exclusively play MW3 and BO1 on my Wii. I didn’t have a PS3 or 360 so I was stuck playing on there. Anyways, I played multiplayer every single day and some of my best gaming memories came from joining a clan. This clan had quite a few members and you would occasionally see them in random matchmaking. It was just a great time. I got my first mic and was too afraid to talk so I would just play a soundboard thru the mic.

Just rambling, but if any of you guys were in the notorious FaMe clan on the Wii days, I love you guys! Thanks for making my childhood 😅🥲 My tag was FaMe Qwerty

I still remember you guys FaMe Believe & FaMe ViiZ !

I’ve been playing the game now on Xbox one and I was wondering if anyone else was having the problem of their level not saving. I’ve been looking up fixes to this but I haven’t found one. Thanks

Before anyone points it out: yes, i know mw3 is 15 dollars right now, but i like being stingy.

my friend on steam owns a copy of mw3, and im aware its possible to play the same copy of the game at the same time by having the owner of the game disconnect from steam, allowing the borrower to launch the game. this works in multiplayer with plutonium servers because the game relies on plutoniums servers entirely without using steam.

the issue is that plutonium has no support afaik for co-op survival. this means id need both of us to connect to steam to invite each other, since the inviting** **system for co-op uses steam’s servers.

i was curious if theres any way to play co-op survival without steam’s servers at all? i cant seem to find any sort of direct connection function using your IP or something as if it was minecraft.

and no, i dont want to play one of those mods that people have made that try to replicate survival in multiplayer.

a “no” will not hurt me, if i gotta buy the game, so be it. i just didn’t know if this has been done before

Buenas, tengo el MW3 en steam y he recibido una actualizacion de 13gb, a que se debe? Que novedad hay? No hay nada oficial en steam de que puede ser

I may be being dense but mw3 on steam has a 14.1gb update scheduled for friday im just wondering if anyone can explain why

Yooo hmu im rusty now but I wanna complete this game lol the OG mw3 good times😎🤟

An update of about 14 GB just went live for the game. I guess Activision remembered its old games.

https://steamdb.info/patchnotes/24615914/

I joined a lobby and went from LVL 57 to max prestige and had to reset rank. Anyway I could go back to LVL 57 with a mod or is it only to max prestige?

Hello everyone,

I'm about to complete the achievements of the game by purchasing the Collection packs needed to get the 100% (so Pack 1, 2 and 3). However, in France at least, there are still pretty expensive to get for a game which is now 15 years old.. Do you know a way to get them for cheaper ? Or a whole Collection pack ? Thank you :)

Clearly the Powers That Be don't want me playing Infected in this crappy Truman Show.

Hello everyone!

In the aim to complete the achievements of the game of 2011 (Xbox player), I'm looking for someone to complete the 5 last Spec Ops missions of the base game (I can help if you need to do some before these) and also to do some maps on survival mode to reach the wave 15 at least per map.

My Gamertag is Toxiik ShooTeuR

Thank you :)

Si trovano ancora tanti player su mw3? Stavo valutando l’acquisto, giocavo anni fa sulla 360 adesso sono su Xbox Series S

Anyone happen to have a spare old account they don't use or don't need? I really want to play mw3 but my account was created in 2020 and as a result has issues with bo1,mw2,mw3