OK, back to not working.
I am beginning to think that playing of youtube videos is the cause rather than something with the play store. As I mentioned, all weekend I was able to download apps from the play store without issue. I never attempted to play a youtube video.
This morning, I'm down in my office and had occasion to click a link to view a youtube clip. It played without issue. I played a few more thinking that I was back in business. All in the same window.
Then, from another browser window in Chrome I launched another youtube clip, and back to the "a problem occurred" error.
Now the playstore is not working either.
So, used playstore without issue for 48 hours or more, played a few videos, played one in a new window and then all stopped working.