The behavior is not normal. A black screen related to Windows Update can be legitimate, but random mouse movement at the same time should also be checked as a possible input-device or security issue.
A practical way to separate the two problems:
- Check whether Windows Update is actually pending or stuck.
- Go to Start > Settings > Windows Update > Check for updates.
- If updates are pending, let them complete.
- If update installation is stuck, restart the PC and run the Windows Update troubleshooter:
- Start > Settings > System > Troubleshoot > Other troubleshooters > Windows Update > Run.
- If the screen goes black again, try the built-in display recovery steps.
- Press Windows + Ctrl + Shift + B to reset the graphics driver.
- Press Windows + P, then P again, then Enter to cycle display modes.
- If the security screen appears with Ctrl + Alt + Del, open Task Manager and restart Windows Explorer.
- If the system appears frozen during update activity, do a full restart.
- Press and hold the power button for 20 seconds.
- After restart, check Windows Update again.
- Check for common update blockers.
- Make sure the Windows Update service is running:
- Press Win + R, type
services.msc, press Enter. - Open Windows Update service.
- Set Startup type to Automatic.
- If it is stopped, select Start.
- Press Win + R, type
- Make sure there is enough free disk space.
- Make sure the Windows Update service is running:
- For the random mouse movement, test hardware and security separately.
- Disconnect and reconnect the mouse, or test with another mouse if available.
- Run Windows Defender multiple times.
- Change the account password as a precaution.
If the black screen happens specifically after updates, Windows documents that blank or black screens after an update are often linked to incompatible drivers or incomplete updates.
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