Story perspectives

Microsoft Windows 11 Update Causes Major Boot Issues

1/27/2026

Summary

Story summary

Microsoft acknowledged a bug in January 2026 Windows 11 security update causing UNMOUNTABLE_BOOT_VOLUME that blocks booting on 25H2 and 24H2.
Microsoft released two emergency updates that do not resolve the boot problem, so users must uninstall them via Windows Recovery Environment (WinRE).
The update also causes sleep issues and problems with certain applications.
Microsoft is pursuing a fix, but the root cause remains unclear, fueling frustration about stability.

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Story summary

Microsoft acknowledged a bug in January 2026 Windows 11 security update causing UNMOUNTABLE_BOOT_VOLUME that blocks booting on 25H2 and 24H2.
Microsoft released two emergency updates that do not resolve the boot problem, so users must uninstall them via Windows Recovery Environment (WinRE).
The update also causes sleep issues and problems with certain applications.
Microsoft is pursuing a fix, but the root cause remains unclear, fueling frustration about stability.