Overview
- KB5121003, released on August 11, has been linked by users to games freezing, EXCEPTION_ACCESS_VIOLATION errors, crashes to desktop, and unexpected system restarts on Windows 11 25H2 and 24H2.
- Microsoft has acknowledged the reports on its Windows release health dashboard and is investigating whether the update or incompatible third‑party software is the root cause while asking affected players to submit Feedback Hub reports.
- Embark Studios flagged a changed kernel driver file, inpoutx64.sys, and published a temporary fix that stops and deletes the inpoutx64 service and removes the driver to restore playability.
- Several players report that uninstalling or rolling back KB5121003 (for example via DISM) also stops the crashes, but that approach leaves systems without that month’s security and stability fixes.
- Early kernel‑dump analysis and user troubleshooting indicate the update may have tightened kernel handle validation so that a pre‑existing 'bad‑handle' in some third‑party drivers now triggers INVALID_KERNEL_HANDLE crashes, which could mean other peripherals or utilities that use inpoutx64.sys may also be affected.