COD Modern Warfare 2 allows players to create private matches, which is a great way to test out new weapons, equipment & whatnot without worrying about other players.
However, some players have been getting game-breaking dev errors (like 401, 292, 11642), which prevent them from joining public or private matches. If you’re also stuck with this issue, don’t worry.
Let’s dive into this article & discuss how to get rid of this private lobby error in MW2.
What is Dev Error 401 in Modern Warfare 2?
401 Dev Error is an error message that occurs due to authentication or authorization issues while trying to access the online servers of the game. This error, along with Dev Error 11642 & 292, usually appears whenever a player tries to create a private lobby.
If you’re constantly having Dev Error 401 while trying to play MW2, the game might be having connection issues. Hence, the game server is not giving your account the proper authentication to create a private lobby or join a public match.
How to Fix Error 401 in COD Modern Warfare 2
To get rid of the Dev 401 Error in MW2, launch the game and go to Settings > Graphics. Then select the Display tab & set the Custom Frame Rate Limit from Custom to Unlimited. You should also disable the VPN and open the Steam client to verify the game files.
If that doesn’t work, there are some alternate methods that you can apply to fix this game error. Below, I have thoroughly discussed all these troubleshooting methods in great detail.
Here’s how to fix dev error 401 in MW2:
1. Change the Custom Frame Rate Limit to Unlimited
Although Infinity Ward (developers of COD MW2) have acknowledged and fixed this error with their Season 1 patch, some players are still facing this issue. In most cases, switching the FPS limit from Custom to Unlimited has somehow resolved the error. So, let’s start with that.
Follow these steps to change the fps limit & fix dev error 401 in COD MW2:
- Launch the game & click on the gears icon to open Settings.
- Select Graphics > Display tab.
- Scroll down & find the Custom Frame Rate Limit option.
- Click on Custom & select Unlimited.
- Hit Apply Settings to save the changes.
Now restart the game and try to create a private session to see whether the error persists or not. This procedure should also help when MW2 keeps crashing. If it does, head over to the next method.
2. Verify the Game Files
If you’ve been playing MW2 since the game launched, there might be some old files from previous patches that might be causing this error. Or, in case you’ve recently updated the game, there might be corrupted game files during the patch installation process.
No matter the reason, verifying the game files from the launcher client can resolve this issue. Here’s how:
For Steam
- Open the Steam client and go to your game library.
- Right-click on Call of Duty: Modern Warfare 2 from the game list and select Properties.
- Click on the Installed Files tab from the left side pane.
- Select Verify integrity of game files.
For Battle.net
- Run the Battle.net launcher and go to your game library.
- Find and select Call of Duty: Modern Warfare 2 and click on the gears icon to open Options.
- Choose Scan and Repair > Begin Repair.
Done! Now, the game client will automatically detect & replace any corrupted files and fix the dev error. It will also check and update the game to the latest version. This method is also effective for dev error codes 11642 and 292 in Modern Warfare 2.
Also, check out what to do when shader optimization gets stuck in MW2.
3. Don’t Use VPN
You should never use a VPN while playing online multiplayer games. It not only adds unwanted latency & packet loss, but some game servers can also flag VPN IPs and prevent players from joining online sessions.
So, in case you’re using a VPN and Modern Warfare 2 private matches are not working, I’d highly recommend disabling the VPN software before launching the game. While you’re at it, restart your router/modem and make sure you have a stable internet connection.
4. Try Joining a Public Matchmaking
The MW2 dev error 401, 11642, and 292 occurs when your request to create a private match gets denied. It happens due to the lack of valid authentication credentials for the target online server.
So, in theory, briefly joining a public match will revalidate your credentials to access official servers. To do that, simply enter a public multiplayer match and play a few rounds. Then, exit the match and try creating a private lobby to see if the dev error has been resolved. 
This method works for both PC and console players alike, especially for Xbox Series S dev error 401 in MW2.
5. Run Modern Warfare 2 in Safe Mode
When the game crashes with an error screen, you should get a pop-up message like Would you like to run it in safe mode? Sometimes, a game can troubleshoot its own error and show you a prompt to fix the technical issue.
If you get such a prompt with the dev error message, click Yes and run MW2 in Safe Mode.
6. Reinstall Modern Warfare 2
If none of the above-mentioned solutions have worked for you and you’re still getting this 401 error in Modern Warfare 2 on PS4, Xbox, or PC, just uninstall and reinstall the game. This method also works for MW2 dev error 11557. Here’s how:
For PC
- Launch Steam/Battle.net and go to your game library.
- Find and right-click on Call of Duty: Modern Warfare 2.
- Select Manage > Uninstall.
For PS4/PS5
- Select Modern Warfare 2 from the game library and press the Options button on the controller.
- Click on Delete.
For Xbox
- Press the Xbox button on the controller and select My Games & Apps.
- Hover over Modern Warfare 2 and press the Menu button on the controller.
- Select Uninstall.
That’s it. Now, go to the respective game store and download/install the game again. If you’re still getting ERROR 401 in private matches, update Windows and the graphics card driver. Also, consider reducing the texture streaming and spot cache from the in-game settings.
Frequently Asked Questions
Why are you getting 401 Error in MW2?
Using VPNs to join multiplayer matches can often spit out Error 401 in COD MW2. This error can also occur due to improper game config, corrupted game files, and poor/unstable internet connection.
Do private matches work in MW2?
Yes. Private matches and bot lobbies work in COD Modern Warfare 2. But you’ll need to do further customization in the lobby to get things going.
What is Dev Error 11642 in Modern Warfare 2?
Dev Error 11642 in COD MW2 indicates an authentication error for private match lobbies. This error occurs when players try to initiate a private match. During the loading process, players get sent back to the homepage with an error 11642 message.
To Sum It Up
Whenever you encounter Dev Error 401 while attempting to create a private match in MW2, simply modify the FPS limit to unlimited from the in-game Graphics settings. Also, verify the game file integrity from the Steam client and keep the game updated. That should do the trick.
If you’re having trouble following this write-up, feel free to ask any questions in the comment section below. Our help team will get back to you in no time.
Adios!
