Which are you using to run the game (Steam, Plutonium, or a retail disc)?
Copy the following folders from an English install:
Do not download language packs from torrents with generic names. Many contain outdated .exe wrappers or malware. Use only community-verified sources. Which are you using to run the game
This is the recommended approach for a full conversion. Look for a release labeled torrent. This pack typically contains the updated main directory and the complete zone/english folder structure with all DLC and update patches already applied.
For those using the Plutonium modded client to play MW3 online, specific patches are available on their community forums that automate much of this process. Why can't I change the language in cod mw3 : r/CrackSupport Use only community-verified sources
Timestamps in .csv differ between regions. Solution: Use a patched english_patch.csv from the latest pack (version 1.9.461 or higher).
This article covers everything you need: what the official/unofficial English language pack is, the crucial "patched" version that fixes broken decryption, step-by-step installation, troubleshooting common errors (0x80070002, corrupt files), and how to ensure multiplayer compatibility after patching. This pack typically contains the updated main directory
This happens when the game engine cannot read the language configuration string.
If you play via Steam and run a file verification check, Steam will automatically overwrite your patched English files with the original regional files.