Microsoft KB5120998 Preview Update Causes Mouse Settings Reset on Non-English Windows 11 Systems
Issue affects systems with non-English language packs; English-language installations remain unaffected
Key Takeaways
- KB5120998 August 2026 preview update causes mouse settings to revert to defaults on non-English Windows 11 systems.
- English-language Windows 11 systems are unaffected by the bug.
- Microsoft is tracking the issue but has not provided an official patch.
- Users can try uninstalling the update or reconfiguring mouse settings post-installation as workarounds.
- No exploitation has been reported; the issue is a configuration reset bug, not a security vulnerability.
Quick answers
- What happened?
- Microsoft has acknowledged a bug in the KB5120998 August 2026 preview update that reverts mouse settings to defaults after installation. The issue is confirmed to impact only non-English Windows 11 systems, while English-language systems are unaffected. No exploitation has been reported, and the issue is described as a configuration reset bug rather than a security vulnerability.
- Which products are affected?
- Windows 11
- What should defenders do?
- Users on non-English Windows 11 systems can uninstall the KB5120998 update or reconfigure mouse settings after installation. English-language systems are unaffected and require no action.
Microsoft has confirmed a known issue affecting the KB5120998 August 2026 preview update for Windows 11. Users installing the update on non-English language packs have reported that mouse settings revert to defaults following installation. The company states the bug is limited to non-English Windows 11 systems, and English-language installations do not experience the issue. Microsoft is currently tracking the issue and has not released an official patch. Workarounds include uninstalling the update or reconfiguring mouse settings after installation. No exploitation of this issue has been reported, and it is not considered a security vulnerability allowing attacker control.
Security Details
Issue: KB5120998 August 2026 preview update causes mouse settings to revert to default after installation on non-English Windows 11 systems. Status: Microsoft tracking the issue; no official patch released. Impact: Configuration reset bug; affects only non-English language packs. Exploitation: None reported.
Affected products
Windows 11
Mitigation
Users on non-English Windows 11 systems can uninstall the KB5120998 update or reconfigure mouse settings after installation. English-language systems are unaffected and require no action.
Sources
BleepingComputer
Microsoft: KB5120998 mouse reset bug affects only non-English PCs
Sep 3, 2026 · 15:22
Original link
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