Windows 11 KB5121003 update is causing game crashes, Windows Hello problems, and HDR issues for some PCs
Microsoft’s mandatory Windows 11 KB5121003 security update is creating frustration for some users, especially gamers. The August 11 update moves Windows 11 25H2 systems to build 26200.9168 and Windows 11 24H2 systems to build 26100.9168. It is an important patch because it fixes more than 420 security vulnerabilities, including an actively exploited zero-day issue known as LegacyHive.
However, despite Microsoft’s release notes currently listing no known issues, users are reporting a growing number of problems after installing KB5121003. The most serious complaints involve sudden game crashes, unexpected PC reboots, Windows Hello PIN failures, black screens, refresh rate problems, and broken HDR behavior.
One of the biggest issues affects players of ARC Raiders and The Finals. After installing the Windows 11 KB5121003 update, some players say the games crash shortly after launch or during gameplay. Others have reported system instability and unexpected restarts.
Embark Studios, the developer behind ARC Raiders and The Finals, has acknowledged the crash reports and said it is investigating the problem. Some affected players have seen error messages such as “hang detected on GameThread” and “EXCEPTION_ACCESS_VIOLATION,” which usually point to a low-level software or driver conflict rather than a standard in-game bug.
According to the developer’s findings, the crashes appear to be linked to inpoutx64.sys, a third-party kernel-level driver used by some hardware utilities. This driver allows low-level port access and may be installed by certain peripheral or system tools. In some cases, users found it was added by software related to device update utilities, including tools used for gaming accessories.
The Windows 11 update itself may not be directly “breaking” the games. Instead, KB5121003 appears to have changed something in the operating system that makes inpoutx64.sys incompatible on affected machines. When the driver is present, games that rely on certain system-level processes or anti-cheat protections may crash.
Reports are not limited to ARC Raiders and The Finals. Some users have also mentioned crashes in Marvel Tōkon: Fighting Souls, along with issues involving anti-cheat software. This suggests the problem could affect more games depending on the drivers and utilities installed on a PC.
For users experiencing game crashes after installing Windows 11 KB5121003, the most effective workaround appears to be removing the inpoutx64.sys driver or uninstalling the software that installed it. Advanced users can stop and delete the inpoutx64 service using Command Prompt with administrator privileges, then remove the driver file from the Windows system32 drivers folder.
That said, deleting system drivers should be done carefully. If you are unsure where the driver came from, it may be safer to uninstall recently added hardware utilities or device update tools first. Restarting the PC afterward is recommended to confirm whether the crashes are resolved.
Gaming problems are not the only complaints tied to the KB5121003 update. Some Windows 11 users are also reporting Windows Hello failures. In certain cases, the PIN must be re-enrolled after every reboot because the credential key becomes corrupted when it regenerates. Other users say the existing Windows Hello container fails to load, preventing normal sign-in behavior.
This can be especially frustrating because Windows Hello is widely used for quick and secure access through PINs, fingerprints, or facial recognition. If the system keeps forcing users to reset their PIN after each restart, the issue can quickly become disruptive for work, gaming, or daily use.
Display-related problems are also appearing in scattered reports. Some users say their monitor refresh rate drops unexpectedly after the update, while others have experienced black screens or broken HDR. These issues may be connected to display changes included in the KB5121003 update, though Microsoft has not yet listed them as official known problems.
If HDR looks washed out, stops working, or behaves inconsistently after installing the update, users may want to check Windows display settings, graphics driver settings, and monitor refresh rate options. Updating GPU drivers may help in some cases, but if the issue began immediately after KB5121003, the Windows update may still be the trigger.
Affected users have a few options. For game crashes, removing inpoutx64.sys or the software that installed it should be the first step. For Windows Hello, HDR, black screen, or refresh rate problems, users can try updating drivers, reconfiguring Windows Hello, or resetting display settings.
Uninstalling KB5121003 is also possible through Settings, Windows Update, Update History, and Uninstall Updates. However, removing the update should be treated as a last resort. Because KB5121003 includes hundreds of security fixes and addresses an actively exploited vulnerability, uninstalling it could leave a PC exposed.
For most users, the safer path is to keep the update installed and wait for an official fix, especially if the PC remains usable. Gamers affected by crashes may be better served by removing the conflicting inpoutx64.sys driver rather than rolling back the entire Windows security update.
Microsoft has not yet added these problems to the official known issues list for KB5121003. Until a fix arrives, users should monitor their system closely after installing the patch, keep graphics and hardware drivers updated, and avoid removing the security update unless the problems make the PC unstable or unusable.
