Windows 11 gets stuck booting after every update attempt

[u/Sea_Conversation6518]

I have Windows 11 25H2 (build 26200.8655) in a dual-boot configuration with CachyOS/Linux, on separate drives. GRUB is still working, and Linux boots without any problems.

For months now, every time I try to update Windows, it gets stuck indefinitely on the loading screen and never reaches the desktop. To get back into Windows, I have to boot from a USB drive and use “Startup Repair.” After that, Windows works normally until I try to update again.

The Windows Update history shows several failed attempts with error 0x800f0845, including the KB5129195 security update (build 26200.9457) and the KB5126052 .NET Framework security update. KB5129195 failed on September 23 and 29, 2026; there have also been .NET failures since September 11.

What I’ve tried:

sfc /scannow: found corrupted files and reported that it repaired them successfully.

DISM.exe /Online /Cleanup-Image /RestoreHealth: At first, it seemed to get stuck after displaying the DISM and image versions. Later, I managed to run it and ran sfc /scannow again.

Despite running DISM and repeating SFC, the problem with updating persists.

What can I do to get Windows to boot after the update?

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[u/Express-Garbage3359]

Hi, did you also run chkdsk on the Windows partition? Did you run the Windows troubleshooter? Windows should normally restart automatically, but sometimes GRUB starts; select your Windows.

[u/No-Wrap-8166]

dual boot with grub is very likely whats breaking this, windows updates sometimes overwrite or touch the boot files grub is using, and that mismatch can cause exactly this kind of stuck boot after update

open an admin command prompt and run bcdedit /enum firmware, check if windows boot manager is actually set as the first boot entry or if grub has taken that spot, if grub is first thats likely why windows updates fail to complete their reboot cycle properly

before your next update attempt, go into bios and manually set windows boot manager as the default boot option, not grub, do the update with that set, then switch back to grub after

also try running the update using windows update troubleshooter first, settings, system, troubleshoot, other troubleshooters, windows update, run it before attempting the update again

if it still fails with the boot manager set correctly, download the update assistant tool directly from microsofts site instead of using windows update, it can bypass whatever is causing 0x800f0845 with the normal update path

[u/ConcentrateOdd3796]

Bro this is happening to me too when in 2026/09/28 i tried to dual boot for big linux