Microsoft Issues Emergency Windows 11 Update to Fix System Recovery Bug

Microsoft released an emergency update for Windows 11 today, October 21, 2025, to address a critical bug that was preventing users from properly utilizing system recovery options.

The issue, which surfaced following recent security updates, specifically impacted USB keyboard and mouse input within the Windows Recovery Environment (WinRE) for versions 24H2 and 25H2 of the operating system. Users reported being unable to navigate or interact with recovery tools, hindering their ability to restore their systems to a working state. This bug could have left many users unable to recover from failed updates or system errors.

The fix, identified as KB5066835, addresses the input malfunction and restores functionality to USB keyboards and mice within WinRE. Earlier reports indicated the update also caused issues with localhost, File Explorer preview pane functionality, and installation errors, which Microsoft is actively working to resolve with further hotfixes. For more information on managing Windows updates, visit the Microsoft Support website.

Microsoft confirmed the problems and is pushing the emergency patch to affected systems. The company stated they are continuing to monitor the situation and will release additional updates as needed to address any remaining issues. Users can also find details about known issues and resolutions on the BleepingComputer website.

Officials stated that further hotfixes are in progress to address the remaining reported bugs and ensure a stable experience for all Windows 11 users.

1. Microsoft’s emergency Windows 11 update fixes a nasty system recovery bug  The Verge
2. Microsoft rushes out emergency Windows 11 patch after botched update breaks Recovery — restores USB keyboard and mouse input inside WinRE for Windows 11 versions 24H2 and 25H2  Tom’s Hardware
3. Hotfixes Are in Progress for Windows 11 Security Updates That Introduced Some Major Bugs  CNET
4. Microsoft confirms Windows 11 KB5066835 issues. Localhost, File Explorer preview, install errors  Windows Latest
5. Microsoft to release emergency fix for Windows 11 update that caused widespread problems  Mashable