Microsoft is confronting a serious issue. The October Windows 11 25H2 update contains a critical bug that can render a PC inoperable.
The defect prevents keyboards and mice from working within the Windows Recovery Environment (WinRE). That means repairing or resetting a PC after a failure becomes nearly impossible.
The problem traces back to patch KB5066835, released on October 14, 2025. Rather than improving security, the update broke the Windows Recovery Environment — the component responsible for launching repairs, rolling back updates, and accessing the BIOS. After installing the patch, USB mice and keyboards stop functioning inside WinRE.
Microsoft has acknowledged the issue. The company says the “problem only affects USB devices in WinRE after the October 14 update” and has promised a fix in the coming days. For users whose systems are already locked, however, that offers little comfort.
The only practical workaround is to use legacy PS/2 ports — which are uncommon on modern motherboards. Experts recommend avoiding installation of the update until Microsoft releases a corrective patch.
Source: iXBT.games