Yes, I have no argument at all with what you and Steve have said. Many thanks for your efforts to date!
Were you able to view the VIDEO 1 and VIDEO 2 attached to my June 13th posting?
The overall indication seems to be that there is something wrong with the Windows 10 Version 20H2 installation on my two computers which have it, and with the third computer running the Windows 10 Home edition that I referred to before. All three are manifesting similar symptoms when I try running SAM on them.
I'm not concerned about the computer which runs the Windows 10 Home edition - it's my wife's, and she doesn't use SAM at all.
If my own installations of Windows 10 Version 20H2 are the culprits in all this, then I could try running another test with SAM Version 2017.9.5 (which of course I've used many times before - with no problem). The same or similar symptoms will likely occur.
If that actually happens then this would tend to further confirm that my problem involves missing or corrupted Windows files. I've no idea how or why that might have happened with my installations of Windows 10 version 20H2 - not on just one computer, but two. Yet at this point it seems to me to be the only plausible explanation for what's happening.
It looks increasingly clear to me that we will need to ask Microsoft about this.
I could also try finding someone here in Ottawa who also uses SAM (and I can't believe there isn't any such person), then I could take screen shots of his lists of Windows files for comparison with mine - to see if there are any Windows files obviously missing in my system. Such a comparison would be useful only the other person's computer is also running Windows 10 Version 20H2. But even if I then find nothing obviously wrong, that would not preclude the possibility of corrupted Windows file(s) on my own machine(s).
If I can find someone here in Ottawa, Canada, who uses SAM and whose computer also runs Windows 10 Version 20H2, I'll let you know. Meanwhile if you can let me know of anyone else like this in Ottawa, that might also help.
Sincerely, Robert T. Chisholm