Windows 11 Update KB5077181 Resolves Boot Failures from Previous Update Errors
Microsoft has addressed a significant issue affecting Windows 11, specifically in commercial systems. This problem involved boot failures triggered by an “UNMOUNTABLE_BOOT_VOLUME” error after the installation of specific security updates.
Background of the Boot Failure Issue
The boot issue stemmed from previous updates, particularly the security update KB5074109 released on January 13, 2026. The problem primarily affected devices running versions 25H2 and 24H2 of Windows 11. Affected users encountered a black screen error message indicating that their devices needed a restart.
Resolution in Update KB5077181
On February 10, 2026, Microsoft released the Windows 11 KB5077181 update during the February Patch Tuesday. This update resolved the boot problems linked to earlier security updates. The company stated that no reports of home users or virtual machines being affected by the issue were received.
Initial Fix Attempt
Prior to the full resolution, Microsoft attempted to mitigate the issue by issuing an optional non-security preview update, KB5074105, on January 29, 2026. This update aimed to prevent further systems from encountering the boot failure problem.
Impact and Recommendations
Despite the release of the fix, some systems that became unbootable prior to this update might still require additional remediation steps. Microsoft has advised enterprise clients whose systems remain affected to reach out to Microsoft Support for Business for assistance in restoring stability.
- Update Title: Windows 11 Update KB5077181
- Release Date: February 10, 2026
- Related Updates: KB5074109 (January 13, 2026), KB5074105 (January 29, 2026)
- Affected Versions: Windows 11 versions 25H2 and 24H2
This advisory was notably not shared publicly, prompting questions about transparency in Microsoft’s communication regarding known Windows issues. Maintaining clear communication is vital in the face of rapidly evolving IT infrastructure and user expectations.
