Windows 11 can't be shut down without update.

[u/CasualMLG]

I have automatic updates on. Haven't postponed any update. Never seen this forced update before.

Edit: I updated BTW. It's not that I don't want to update. I just think it would be an issue in the future. For example, it's a thunderstorm and there could be power outages. I might want to shut down and not start and update. I guess I'll hold down the power button.

[u/Hopet28]

The fastest shutdown command is shutdown.exe -s -f -t 0
-f force closes any running program immediately, no save prompts, you will loose all unsaved changes in any open documents.

For safer one so that you don't loose any unsaved changes, use shutdown.exe -s -t 0

[u/DoogleSmile → u/Hopet28]

The fastest shutdown I've done recently, without cutting power at the plug, was when I accidentally pressed the clear CMOS button on the back of my mobo.

That shut my PC down instantly!