wrote:
There in lies the rub.

My updating has been non-functional for a very long time.

It just indicates failed to update.

All my efforts at diagnosis and possible remedy have failed.

However there doesn't seem to any significant consequences for this.



That button is not Windows Update.

That button is an NTP time update.

You can open Command Prompt and do

nslookup time.windows.com

and see whether DNS resolves properly.

These nodes don't necessarily respond to "ping", because
that would enable various denial of service scenarios.
I can't guarantee that every time server is ping-able.

It could be that some service isn't running. Using
"services.msc" as an executable, look and see if "Windows Time"
service is running at the moment. Start it. GO back to the Update
button and try again.

Paul