I'm back on line and on the computer. Actually, I was on line when the computer was away to the shop by going on other computers elsewhere. Or on my phone. I was charged for 4 hours of work, but the fix took them, they said, over 40 hours. No wonder they aren't making a good living at this work! After I got the computer back, I still had to go in and get lots of the data and files from my portable hard drive, and copy them back to the clean hard drive in the computer. I also had to make sure all the old emails and contact lists were reinstalled, as well as some programs that I use. Very time consuming.
What I learned: If you get a pop-up that might look like it is from Microsoft or some other supposedly trusted site, that doesn't mean that it is legitimate. I knew right away that what I had was a fake. The mistake I made was trying to click the X to get rid of it. DON'T DO THAT. Just shut down the computer in the normal way, immediately. The computer tech told me he had the same pop-up the day before I picked up the computer. It infected the hard drive as well as my external back up drive. What a mess.