First thanks to dalchina and AddRAM.

To get system back I used an ISO which was the same as version I had installed.

I disabled Secure Boot in the bios and turned off the firewall and...

Looks as though it is good news.

Started with Version 2004 (OS Build 19041.746) 64 bit - No updates

This time I used an ISO for 2004. This time it worked and kept all data and apps.

This...

The best I can come up with is an Easus ISO dated 18 Jan 2021.

This is before

Last update that went through:
MS Office 2010 (KB4493143) 32 bit
03/02/21

Hard Disk Sentinel

The status of the solid state disk is PERFECT. Problematic or weak sectors were not found. The TRIM feature of the SSD is supported and enabled for optimal performance.
...

The error can be generated because a function called, secure boot is enabled. Which does not allow the update to be carried out correctly, or it can also occur when there is corruption in the Windows...

20H2 was one coming up in auto update. I could try that one.

Yes opened and ran setup.

It put itself back to where it was at start.

Have not used Sentinel yet but results of chkdsk:

C:\WINDOWS\system32>chkdsk c: /scan
The type of the file system is NTFS.
Volume label is Windows.

Stage 1: Examining basic file system...

Windows logs not giving any clue nor the troubleshooter.

No restore point that far back.

Running Reset WIndows Update gives:
ERROR: The system was unable to find the specified registry key or...

Thank you for info.

First tried that thread you mentioned with no luck.

SetupDiag is giving me a blank log.

Net Framework is ver 4.8.04.84

Keith

Version 2004 (OS Build 19041.746) 64 bit

I've tried everything from Google searches.

Last update that went through:
MS Office 2010 (KB4493143) 32 bit
03/02/21

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