Hi Greg,
I've removed the AVG with remover downloaded. Check by sfc, everything OK. Windows Defender is on.
Then install MalwareBytes and run the scan once, with no detection returned. Program turned to free version with real-time protection set to off.
In going through the steps for Repair Install, I note from your previous message that in running the Media Creation Tool, select "Upgrade the PC now".
However, according to the tutorial you suggested, it instructs to select "Create Installation Media.....".
Which selection should I make?