• Windows 11 KB5077181 fixes boot failures linked to failed updates February 15, 2026 05:08 PM 0 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. • The boot issue, which Microsoftpreviously investigatedand linked to failed December 2025 updates, affected a limited number of commercial Windows 11 devices running versions 25H2 and 24H2. • According to a private enterprise advisory seen by Susan Bradley of Ask Woody, the issue has now been marked as fully resolved in the Windows 11 KB5077181 security update released on February 10, 2026. • Microsoft says impacted devices suffered boot failures after installing the January 13, 2026, security updateKB5074109or later updates, displaying a black screen and the message: “Your device ran into a problem and needs a restart. • You can restart.” At that point, impacted systems were unable to boot and required manual recovery to restore functionality. • Microsoftpreviously confirmedthe issue was caused by the failed installation of the December 2025 security update, leaving devices in an improper state after the installation rolled back.
Article Summaries:
- 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. The boot issue, which Microsoft previously investigated and linked to failed December 2025 updates, affected a limited number of commercial Windows 11 devices running versions 25H2 and 24H2. According to a private enterprise advisory seen by Susan Bradley of Ask Woody, the issue has now been marked as fully resolved in the Windows 11 KB5077181 securi
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