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Microsoft is investigating reports that August Windows 11 security updates may be causing some games to fail to launch, freeze, crash, or trigger unexpected system restarts. Affected users have reported symptoms including unexpected game closures and the EXCEPTION_ACCESS_VIOLATION error, with incidents tied to Windows 11 versions 25H2 and 24H2 after installation of update KB5121003 and later releases.
Named titles in user reports include ARC Raiders, MARVEL Tōkon: Fighting Souls, and The Finals. Microsoft said it has not yet confirmed the root cause and is asking impacted users to submit diagnostics through the Feedback Hub while the investigation continues. No workaround has been issued, and users are being cautioned against uninstalling the updates because they also fix security vulnerabilities, including some that are already being exploited.
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Microsoft advised affected Windows 11 users to manually disable the problematic inpoutx64-related driver through Registry Editor as a temporary mitigation for crashes, freezes, and restarts tied to the August KB5121003 update. Embark Studios shared the same workaround for ARC Raiders and The Finals while Microsoft continued investigating the issue.
Microsoft said the post-August 11 Windows gaming crashes appear to be associated with drivers or code components installed by RGB-enabled peripherals or internal devices, including files with names similar to inpoutx64. Embark Studios separately said crashes affecting ARC Raiders and The Finals are related to inpoutx64.sys and shared a temporary workaround pending an official Microsoft fix.
Microsoft published an acknowledgement in its Windows Release Health dashboard saying it is investigating whether the August Windows security updates caused gaming stability problems. The company also asked affected users to submit reports through the Feedback Hub and said no workaround was yet available.
After the August 11, 2026 Windows updates, Microsoft received reports that some games on Windows 11 24H2 and 25H2 failed to launch, froze, crashed, showed EXCEPTION_ACCESS_VIOLATION errors, or triggered unexpected restarts. Named affected titles included ARC Raiders, MARVEL Tōkon: Fighting Souls, and The Finals.
Microsoft released KB5121003 as part of the August 2026 Patch Tuesday Windows security updates. The update included security fixes as well as Secure Boot, File Explorer, and Windows Search changes.
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Microsoft's cumulative Windows 11 update **KB5121003** introduced security improvements and expanded deployment of new Secure Boot certificates, while the company said it was not aware of any known issues. After installation, however, users and game developer **Embark Studios** reported crashes affecting titles including **ARC Raiders** and **The Finals**, with symptoms including `EXCEPTION_ACCESS_VIOLATION`, `Hang detected on GameThread`, anti-cheat failures, black screens, refresh-rate drops, broken HDR behavior, and in some cases full system reboots. Reports indicate the failures are tied to a compatibility conflict involving **`inpoutx64.sys`**, a third-party kernel-level port access driver used by some hardware utilities and applications. Embark published a workaround that removes the associated service and driver file, while some users said uninstalling **KB5121003** restored stability, reinforcing signs of a driver-update conflict rather than a game-specific defect.
Aug 25, 2026
Microsoft’s January Windows 11 cumulative update **KB5074109** has been linked to gaming performance degradation and instability on systems using **NVIDIA GeForce** GPUs, with users reporting **15–20 FPS drops**, **black screens**, and **visual artifacting** after installation. NVIDIA acknowledged the issue publicly via its GeForce forums, stating it is investigating and that uninstalling `KB5074109` appears to be the only effective temporary mitigation; some users also report that installing Microsoft’s latest optional updates may resolve the problem without removing the security update. The update is described as **security-critical** (reported as addressing **114 vulnerabilities**), creating a tradeoff between stability and exposure if the patch is removed. Separately, Microsoft has been issuing multiple **out-of-band (OOB)** fixes following January Patch Tuesday to address regressions (e.g., Remote Desktop credential prompt failures and Outlook Classic `.pst` access issues on cloud storage) and also shipped an OOB fix for an Office zero-day (**CVE-2026-21509**, a security bypass), underscoring a broader pattern of post-release remediation activity around the January patch cycle.
Jul 12, 2026
Microsoft’s January 2026 Patch Tuesday release for Windows 11 (notably **KB5074109** for 24H2/25H2) delivered roughly 100+ security fixes (including reported **zero-days**) but also introduced significant reliability regressions. Reported impacts include **system lockups**, **black screens** on systems with Nvidia/AMD GPUs, graphics-related hangs in GPU/DirectX-intensive applications, and application failures such as **Outlook Classic** freezing or failing to launch; additional issues were reported with File Explorer behavior and cloud-backed storage workflows (e.g., OneDrive/Dropbox) causing apps to become unresponsive when saving or syncing data.
Jun 29, 2026