Overview
- KB5121003, which rolled out on Aug. 11, 2026, has been linked to game freezes, EXCEPTION_ACCESS_VIOLATION errors, crashes and unexpected restarts on a limited number of PCs.
- Microsoft has confirmed it received reports and is investigating the issue while asking affected users to submit Feedback Hub reports to help reproduce the problem.
- Embark Studios identified the kernel driver file inpoutx64.sys as likely involved and published a temporary workaround that stops and deletes the driver to restore gameplay.
- Reports and testing show the problem has appeared on Windows 11 24H2 and 25H2 installs and has primarily affected ARC Raiders, MARVEL Tōkon: Fighting Souls, and The Finals while 26H1 appears unaffected so far.
- Some users say uninstalling or rolling back KB5121003 restores normal play but removing inpoutx64.sys can disable related peripheral software and carries risk, so players should weigh the tradeoffs and await an official Microsoft fix.