Windows 11 KB5074109 update: Microsoft advises rollback

Microsoft’s January 13, 2026, cumulative update for Windows 11 is drawing growing complaints from users who say their systems became unstable immediately after installing it. The update, KB5074109, advances Windows 11 25H2 and 24H2 to OS builds 26200.7623 and 26100.7623 and includes security and reliability fixes, including a power-related fix for some devices with a Neural Processing Unit (NPU).

As reports of failures accumulated, Microsoft support guidance and public troubleshooting threads increasingly treated uninstalling the update as an acceptable mitigation for users who were affected.

What users say broke after installing the January patch

Users across Windows communities have linked a range of recurring problems to the January update, with some issues appearing limited to certain configurations.

Some users reported random black screens or display instability after installing the update, with reports often involving PCs using NVIDIA graphics hardware. In more severe cases, users said they had to recover through Safe Mode or the Windows recovery environment to remove the update and restore normal startup.

Others reported that apps refused to launch and threw error codes such as 0x803F8001. Reports have included Windows apps like Notepad and Snipping Tool, as well as third-party utilities and vendor software.

Outlook Classic problems acknowledged by Microsoft

Microsoft has also acknowledged issues affecting “classic” Outlook after the January 13 Windows updates. The company said some users with POP account profiles—and profiles that include PST files, particularly when those PSTs are stored in OneDrive—may see Outlook hang and fail to exit properly, which can prevent the app from reopening normally.

Microsoft’s published guidance for affected Outlook users includes workarounds such as moving PST files out of OneDrive or using alternate access methods until a permanent fix is available.

Other fixes arrived out of band, but not all complaints are resolved

In the days following Patch Tuesday, Microsoft issued emergency out-of-band updates for specific regressions, including problems tied to Remote Desktop sign-in failures and certain shutdown-related issues on Windows 11 23H2.

However, user reports involving black screens and app-launch failures on Windows 11 24H2 and 25H2 have continued, and some users also describe sleep and resume problems on certain hardware. Those power-state reports vary by device and configuration, and Microsoft has not broadly confirmed them in the same way it has for the Outlook POP/PST issue.

Should you uninstall, or keep the update installed?

If your PC is running normally after the January update, many experts advise leaving it installed so you keep the latest security protections and fixes included in the monthly release.

If you began seeing stability problems immediately after KB5074109 was installed... such as black screens, persistent app failures, or Outlook Classic hangs... uninstalling the update is now widely cited as a supported stopgap while Microsoft works on a more complete fix. The standard removal path is through Settings, under Windows Update history, followed by a restart. If a system won’t boot normally, the update can also be removed from the Windows recovery environment.

Microsoft and many security professionals continue to warn that rolling back a security update can increase exposure to patched vulnerabilities. For users facing repeated crashes or unusable productivity apps, though, the practical guidance has become more blunt: stabilize the machine first, then reapply fixes once Microsoft delivers a corrected build.