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English => News => Topic started by: Redaktion on January 26, 2026, 20:54:15

Title: Windows 11 KB5074109 now linked to boot failures
Post by: Redaktion on January 26, 2026, 20:54:15
Microsoft's troubled Windows 11 KB5074109 January 2026 update is now under investigation for causing UNMOUNTABLE_BOOT_VOLUME boot failures on some systems. Affected PCs refuse to start and must be recovered via WinRE, adding a serious new symptom to an already messy Patch Tuesday.

https://www.notebookcheck.net/Windows-11-KB5074109-now-linked-to-boot-failures.1212711.0.html
Title: Re: Windows 11 KB5074109 now linked to boot failures
Post by: tfk, the5krunner on January 26, 2026, 21:44:34
this update is a disaster causing everyone here multiple problems.
uninstall fixes it but I've spent over a day fixing corrupted pst files for me and some others.