Windows 11 patch breaks 'Reset this PC'

Microsoft has confirmed that some Windows 11 machines can no longer use “Reset this PC” after recent hotpatch updates, breaking a core recovery tool built into the operating system. (support.microsoft.com) The affected update is KB5079420, a March 10, 2026 hotpatch for Windows 11 versions 24H2 and 25H2, on OS builds 26100.7979 and 26200.7979. Microsoft added a known-issues note saying “Reset this PC might fail with the March 2026 Hotpatch security update or later.” (support.microsoft.com) Microsoft’s February 10, 2026 hotpatch, KB5077212, shipped a month earlier for the same Windows 11 versions and initially listed no known issues. Microsoft has also been cited as linking the reset failure to that February hotpatch on some systems. (support.microsoft.com, neowin.net) “Reset this PC” is Windows’ built-in reinstall option. Microsoft says it can reinstall Windows while keeping personal files, or wipe apps, settings, and files for a full reset. (support.microsoft.com) That makes the bug a recovery problem, not just an update annoyance. Microsoft’s recovery guidance lists Reset as one of the main tools for fixing a machine that is unstable, won’t boot properly, or needs a clean reinstall without separate installation media. (support.microsoft.com) The update type matters here too. Microsoft describes hotpatch updates as monthly security updates that install without requiring a restart, aimed at Windows 11 Enterprise and other managed devices enrolled through Windows Autopatch. (learn.microsoft.com) Microsoft has already published a related fix on the recovery side: KB5079471, a Safe OS Dynamic Update released March 10, 2026, which “makes improvements to the Windows recovery environment,” or WinRE, the repair system that runs outside normal Windows. (support.microsoft.com) That Safe OS update installs through Windows Update, the Microsoft Update Catalog, or Server Update Services, and Microsoft says admins can verify it by checking for WinRE version 10.0.26100.8031. (support.microsoft.com) Microsoft has not posted the reset failure on the public Windows 11 24H2 known-issues page, which currently shows other March 2026 issues and resolutions instead. That means home users may see the problem first in update notes or support channels rather than on the main release-health dashboard page. (learn.microsoft.com, support.microsoft.com) For now, the practical effect is simple: on affected Windows 11 24H2 and 25H2 devices, one of Microsoft’s standard repair buttons may not work when users need it most. Microsoft’s own documentation now points affected systems toward updated WinRE components as the path back to a working reset process. (support.microsoft.com, support.microsoft.com)