Check SUR reoprted no errors (below). With that achieved, I went and tried Windows Update. The updates all failed as follows:
All fail with the same error:
I then rebooted, and tried:
I have attached the CBS.log which shows errors.
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Checking System Update Readiness.
Binary Version 6.1.7601.22471
Package Version 26.0
2021-01-04 12:36
Checking Windows Servicing Packages
Checking Package Manifests and Catalogs
Checking Package Watchlist
Checking Component Watchlist
Checking Packages
Checking Component Store
Summary:
Seconds executed: 324
No errors detected