By Zak Doffman
Publication Date: 2026-01-25 19:11:00
PCs are now failing to start.
NurPhoto via Getty Images
Just when you thought it was safe to update your PC and get back to work, there’s another warning about January’s mandatory security update. You’ll know if you’re affected, because your PC will show you nothing but the Black Screen of Death.
“According to Microsoft,” Windows Latest reports, “affected PCs could suddenly stop booting and land on the Black Screen of Death (BSOD) error with stop code UNMOUNTABLE_BOOT_VOLUME.”
Microsoft says it has “received a limited number of reports of an issue in which devices are failing to boot.” It has asked affected users and admins to report issued. In reality, it’s too soon to know how widely this impacts. All update issues start as “limited” numbers, but then it becomes clear with some that it’s much more widespread.
Thus far we know it affects both Windows 11 25H2 and Windows 11…
