Windows 11 KB5074109 (January 2026 Update) is causing major issues on some PCs, and Microsoft has more details to share.

Microsoft is investigating reports that some Windows 11 devices are failing to boot with "UNMOUNTABLE_BOOT_VOLUME" errors ...

In confirmed cases, Windows 11 boot failure occurs post-update, with the machine stuck at a black screen and unable to ...

Microsoft is aware of an alleged issue that leaves PCs unable to boot and requires manual recovery after Windows 11 January ...

Microsoft is investigating reports of serious boot failures affecting Windows 11 devices following the January 2026 security ...

Forbes contributors publish independent expert analyses and insights. Davey Winder is a veteran cybersecurity writer, hacker and analyst. As if things weren’t bad enough for Microsoft Windows users ...

Windows 11 KB5074109 is causing crashes, reboots, black screens, and BSOD errors for some users, but workaround is available.

Microsoft issues second emergency patch for Windows this month - update your PC today ...