Just to finish off : After deleting OnlineArmor Free firewall and ProgramGuard, system returned to normal operation.
Been running tests and scans all day - nothing found.
Screenie of the CLI - SFC /SCANNOW command - nothing found.
Zip file is an XML output of Windows Reliability Reports that shows .NET Framework 4 updates failed at the time, either/or with OA interactions. Once OA was removed, updates were successful.