Windows 11 KB5077181 fixes boot failures linked to failed updates
Over Security - Cybersecurity news aggregator [Unofficial]
February 15, 2026
Microsoft says it has resolved a Windows 11 bug that caused some commercial systems to fail to boot with an "UNMOUNTABLE_BOOT_VOLUME" error after installing recent security updates, with the fix delivered in the February 2026 Patch Tuesday update.
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