0x80070020
A file is in use by another program, so Windows cannot replace it. Antivirus and backup tools are the usual cause.
How to fix it
- Restart the PC and run the update before opening other programs.
- Temporarily turn off third-party antivirus and backup software.
- Still failing: do a clean boot (
msconfig> Services > Hide all Microsoft services > Disable all) and update again, then undo the clean boot.
Is it serious?
Fixable without repairs.