MW2 - ERROR- Different ingame languages, cant play Special Ops

This workaround should also work for versions with different language than Russian. For instance, the German version should change “localized_english_iw”XX”.iwd” to “localized_german_iwXX.iwd”, the line in localization.txt from english to german and as well for the folder name.

How to change the language of a foreign version of MW2, into English. This should also fix the “Different Protocol” problem/error these players where facing, which is caused due to the different ingame languages of players trying to play a Special Ops game together (for instance an English VS a Russian, German, French version).

Below an updated workaround on how to change the language of the Russian version of MW2 back into English again.

Install Steam with English language
Set language of game into English (in Steam game settings)
Install COD MW2 with Russian Language from DVD
Run game
Exit game & Exit Steam
Get yourself the following files from working English version of COD MW2 (10.9GB): - Folers: “main”, “zone” - All separate files from “***SteamSteamAppscommoncall of duty modern warfare 2″
If asked, replace/overwrite all files with the files from nr. 6
Verify Integrity Cache for COD MW2
Copy all files from English version to folder again
Open file: localization.txt and change first line “english” to “russian”. (If you don’t have this file, you can download it here. Put it right next to youre “iw4sp.exe” in the mwf2 folder.)
Rename localized_english_iw00.iwd to localized_russian_iw00.iwd” (and all other files similar to this too) .
Run Game (fails)
Go to folder: “***SteamSteamAppscommoncall of duty modern warfare 2″
Open folder: “**SteamSteamAppscommoncall of duty modern warfare 2zone” and delete folder “russian”
Rename folder “english” to “russian”
Open Steam and run COD MW2 MP or SP, now with English Language (Text and Voices)