Here I am back after the fight with my desktop and laptop. After trying various things, it turns out that Zone Alarm was the culprit. Somehow, the Microsoft update moved my ZA internet security up to HIGH, rather than the MED where I had set it. Somehow it did NOT do this on my laptop! Go figure...

In the middle of all this bedlam, there was a large scale DSL outage in my area involving fiber or some dang thing - which helped to confuse the issue considerably.

Anyway, thanks for the help. 8 Pints was exactly right.