For those who are playing on the PC, I would recommend doing the following:
Delete your MW3 Multiplayer config file:
1. Open Windows Explorer and navigate to: C:\program files\steam\steamapps\common\call of duty modernwarfare 3\players2
2. Locate and delete config_mp.cfg
Next, Verify the File Integrity of your game within Steam:
File Integrity Check:
1. Load Steam
2. From the Library section, right-click on the game and select Properties from the menu.
3. Select the Local files tab and click the Verify integrity of game cache... button.
4. Steam will verify the game's files - this process may take several minutes.
5. Once the process is completed, the Check Window will automatically exit.
This process will force the game to download and update any files that could be causing issues within the game.
