Dev Error 5820 and its variants became persistent annoyances for Call of Duty: Modern Warfare 3 players. This error disrupts the gameplay experience across MW3, Warzone, and even Zombies, surfacing at the most inopportune moments, either mid-match or just as you are about to queue into a game.

When you receive a dev error, you’ll also notice a lack of explanatory text, which further adds to the overall confusion. While the MW3 developers had plenty of time to identify and address the root cause of dev error 5820, different variants continue to show up after new patches. As a result, the CoD community has been testing and sharing various potential fixes across community hubs, and here are the best fixes you can try to solve the dev error 5820 in MW3 and Warzone.