Recently, a large number of Warzone players started reporting a Dev error 6634 issue that gets them booted in the middle of the game. Though the cause of this issue varies from person to person, we’ve put together some fixes that prove working for many players. Try them and get your game working right away.

Try these fixes

You might not need to try them all. Simply work your way down until you find the one that does the trick.

  1. Scan and repair your game files
  2. Update your graphics driver
  3. Install all Windows updates
  4. Reinstall all shaders
  5. Change your loadouts, skins and operators
  6. Change to another account

Fix 1: Scan and repair your game files

The dev error might indicate an integrity issue with your game files. So instead of reinstalling the whole game, you can start from doing a scan and repair. If you don’t know how, simply follow these instructions:

  1. Open your client.
  2. From the left menu, select Call of Duty: MW. Click Options and select Scan and Repair.
  3. Click Begin Scan. Then wait for the checking to complete.
  4. Once done, enter the game and play as you normal would.

If the issue reoccurs after a scan and repair, you can take a look at the next fix.

Fix 2: Update your graphics driver

Crashes in COD series are usually graphics-related — It could mean your game encountered a compatibility issue triggered by a broken or outdated graphics driver. That’s why we always recommend gamers to keep their drivers up to date: new drivers improve your gaming experience and most importantly, they would also fix compatibility issues like lagging and constant crashing.

There’re mainly 2 ways you can update your graphics driver: manually or automatically.

Option 1: Update your graphics driver manually

If you’re a tech-savvy gamer, you can spend some time updating your GPU driver manually.

To do so, first visit the website of your GPU manufacturer:

Then search for your GPU model. Note that you should only download the latest driver installer that’s compatible with your operating system. Once downloaded, open the installer and follow the on-screen instructions to update.

If you don’t have the time, patience or computer skills to update your video drivers manually, you can, instead, do it automatically with Driver Easy. Driver Easy will automatically recognize your system and find the correct drivers for your exact graphics card, and your Windows version, and it will download and install them correctly:

  1. Download and install Driver Easy.
  2. Run Driver Easy and click the Scan Now button. Driver Easy will then scan your computer and detect any problem drivers.
  3. Click Update All to automatically download and install the correct version of all the drivers that are missing or out of date on your system.(This requires the Pro version – you’ll be prompted to upgrade when you click Update All. If you don’t want to pay for the Pro version, you can still download and install all the drivers you need with the free version; you just have to download them one at a time, and manually install them, the normal Windows way.)
The Pro version of Driver Easy comes with full technical support. If you need assistance, please contact Driver Easy’s support team at

After updating your graphics driver, restart your PC for it to take full effect. Then join a game in Warzone and test the gameplay.

If the latest GPU driver doesn’t stop the crash, you can try the next fix below.

Fix 3: Install all Windows updates

Microsoft rolls out Windows updates periodically, which includes security patches and some nice-to-have new gimmicks. In addition to drivers, you should also make sure your system is up to date so as to avoid some strange issues.

Here’s how you can check for updates manually:

  1. On your keyboard, press Win (the Windows logo key). At the bottom left corner of your screen, click the gear icon to open Settings.
  2. Scroll down and select Update & Security.
  3. Click Windows Update.
  4. Click Check for updates. Then wait for the process to complete. After that, restart your PC.
To make sure you’ve installed all the system updates, repeat these steps until it prompts “You’re up to date” when you click Check for updates again.

Once you’ve installed all the Windows updates, restart your PC and check if error has disappeared.

If Warzone crashes with the same error again, you can try the next method below.

Fix 4: Reinstall all shaders

Shaders refer to a type of program used largely for rendering of different pixels. Some players reported that reinstalling shaders could be a potential fix for the dev error, so you can try the same and see if it helps.

To do this, simply follow these steps:

  1. Launch Modern Warfare and go to Options.
  2. Navigate to the GRAPHICS tab. Click Restart Shaders Installation.
  3. Click RESTART to proceed.
  4. Wait for the process to complete. Then restart your game and test the gameplay

If reinstalling shaders doesn’t give you luck, simply move on to the next fix.

Fix 5: Change your loadouts, skins and operators

The dev error could also be a glitch inside the game. According to some players, changing to Modern Warfare loadouts seemed to have stopped the error from appearing. So if you’re using loadouts or operators from Black Ops Cold War, change them to the Modern Warfare ones and check the outcome. In the meantime, remove all your skins.

BOCW Operators
For the full list of BOCW operators, you can check out this page.

If this trick doesn’t stop the crash, check out the next fix below.

Fix 6: Change to another account

There’s also feedback showing that the dev error 6634 issue might be limited to certain accounts. So if possible, consider testing another account on the same computer. If the problem disappears after changing the account, then you need to compare the difference between two accounts, including but not limited to loadouts, skins and operators.

None of the fixes helps you? Continue to this post for more advanced solutions.

So these are the fixes for your Dev Error 6634 issue in Warzone. Hopefully they help you fix the crash and get back to the field. If you have any questions or suggestions, feel free to jot them down in the comments.

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Werden Sie vom Spiel in Call of Duty: Warzone herausgeworfen und erhalten Sie DEV ERROR 6634? Probieren Sie die 4 Lösungen hier aus!
si vous rencontrez l'erreur critique 6634 du jeu COD: Warzone, vous pouvez essayer les 5 solutions dans notre article pour le résoudre.
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