Hello John,
This worked. I believe the reason it worked is that the initial bloatware was not included in the Windows 11 download. The computer originally came with a trial subscription to Norton. Once that was uninstalled, the virus and threat protection flow either broke or was locked down by Microsoft. I now have a computer I can configure for one of our employees, and continue using Windows Security. (At least until Microsoft makes another change.) Now I’ll install all of the various updates and see if it continues to work, as it did for you.
Thanks for the assistance!