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Call of Duty: Modern Warfare Dev Error 6456 fix

Yet another dev error code is frustrating both Call of Duty: Modern Warfare and Warzone fans. Dev error 6456 has begun appearing when players try to launch the game, alongside a warning saying DirectX has encountered an unrecoverable error. What does Modern Warfare dev error 6456 mean, and what can you do to fix it? Read on to find out.

Modern Warfare Dev Error 6456 | How to fix

modern warfare warzone dev error 6456 how to fix

The Warzone and Modern Warfare dev error 6456 implies there’s a problem with your current version of DirectX. However, it seems this dev error doesn’t have anything to do with GPU drivers or software. Instead, error code 6456 appears to be a bug related to third-party software overlays.

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According to numerous reports on the Activision forums, dev error 6456 appears when users are running outside software such as Discord or NZXT Cam. For whatever reason, the overlays used by these programs create a problem that prevents the game from launching. NZXT Cam seems to be the main culprit, as several users have reported that disabling the NZXT Cam overlay prevents dev error 6456 from appearing.

If you encounter dev error 6456, look through your running programs and disabling any that have an in-game overlay. If you happen to use Discord to communicate in-game, it may be best to switch to the Discord mobile app until the issue has been resolved.

In the off chance that you don’t have Discord or NZXT Cam on your computer, it’s worth checking to make sure your GPU drivers are up-to-date. The warning about DirectX encountering an unrecoverable error is shared with dev error 5759, which often appears when when running older drivers or past Windows updates.

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Barring all else, it’s also worth using the Scan and Repair tool through the Battle.net launcher. With the game selected, click on the Settings icon, then choose Scan and Repair. Any inconsistencies with the game files will be addressed, and any required data will be downloaded and installed.

For most players, the Call of Duty: Modern Warfare dev error 6456 can be fixed by disabling third-party software with in-game overlays. If you have NZXT Cam or Discord running when launching the game, simply close the program and try again. If the problem persists, it’s worth opening up a ticket with Activision support.