Since last Friday, my computer has tended to present me with the Black Screen of Death (BSoD) at odd times. Whereupon I would shut down and the computer and try for a cold start. I would get the Dell Computer logo, followed by the screen that indicated the system was attempting to load Windows 10. Then, most times, I got the BSoD again.
After all my best efforts failed utterly, I called my friend Mike, whose knowledge of hardware and system software far exceeds mine. After a couple hours of going back and forth on the phone, it seems that the Dell Optiplex 9010 had system software that did not match some of the more recent application software. So we upgraded the system software, and suddenly the BSoD was a thing of the past.
Computers are complicated. Fortunately, I do not mind spending the money to get really good advice. Otherwise, I would be one of those millions of people who lose all their files when they unnecessarily migrate from one computer to another.