Windows 11 update KB5121003 is crashing popular games
Microsoft confirms KB5121003 causes crashes in Arc Raiders, The Finals and Tokon: Fighting Souls
Microsoft has confirmed that its August Patch Tuesday update for Windows 11 is causing games to crash on some PCs.
The KB5121003 update, released August 11 for builds 26200.9168 and 26100.9168, introduces a bug that triggers EXCEPTION_ACCESS_VIOLATION errors and, in some cases, restarts the PC entirely mid-session.
Arc Raiders, Marvel Tokon: Fighting Souls, and The Finals have been identified as games responsible for sending crash reports to Microsoft; however, Microsoft emphasises that the list is not exhaustive.
The developer of Arc Raiders and The Finals, Embark Studios, believes the source of the issue to be inpoutx64.sys, an external kernel-mode driver often loaded by peripheral device utilities, including Razer’s own.
According to Embark, there was something about the KB5121003 patch which stopped it from working properly with the driver, causing game crashes.
A separate Reddit user performed an analysis of his kernel dump file and identified a "bad-handle bug", which results from the fact that the updated kernel now validates its handles more strictly.
The update is also breaking Microsoft's own software on Arm devices. According to a Microsoft Learn post from Brian Stringfellow, Teams crashes shortly after opening and the new Outlook fails to launch entirely on Arm64 systems after installing KB5121003, though the classic Outlook app still works.
Stringfellow reported the issue on a Snapdragon-powered Surface Laptop 7th Edition, and other users have confirmed matching problems on the HP OmniBook 3 and Surface Pro 11.
A similar bug appeared earlier this year with KB5094126 and was resolved by rolling back that update before resurfacing with this release.
Microsoft has not suggested any solution to these problems, but it has acknowledged that the crash in games problem affects Windows 11 24H2 and 25H2 and is currently investigating if the update itself or some other program is causing this issue.
Embark, on the other hand, has released their own temporary solution which involves removing the incompatible inpoutx64.sys file. Some of the affected people state that reverting to KB5121003 using DISM will stop all the crashes completely.
Some people have turned off Windows Update for up to a month to avoid having the patch installed again. Reverting to KB5121003 removes over 400 security patches along with the update.
