A restart screen can take longer during updates, but a repeatable loop needs context. Avoid forcing power off repeatedly while an update may be applying.
Protect your files first
Back up important files when possible. If the drive is encrypted, locate the BitLocker recovery key before recovery changes. Stop if storage appears to be failing or this is a work or school managed PC.
What to record
How long the screen has been unchanged, update activity, disk activity, and whether this happens every restart.
The exact message, Windows version, and whether the desktop still opens matter more than a guess based on the symptom name.
Try these safer checks
Check the update context and note the Windows build. If the device eventually boots, save files and inspect update history before another reboot.
Change one thing at a time. After each check, see whether the same symptom returns and write down what changed.
When to stop and get help
If the machine is managed, ask IT before interrupting a scheduled update or recovery operation.
If this is a work or school device, contact its administrator before changing managed settings.
Keep track of your checks
This checklist stays in this browser session. It is not sent to WinErrors.