Sorry, I just realized that I did not reply to your message. The value was "OS VERSION REG_DWORD 0x0000000b (11)."
Since my last post, I gave up and used the recovery drive to restore the computer to its initial state. I then reinstalled MC18 as the first software installed on this computer. MC18 is now functioning normally (thank goodness). I have found, however, that there is some kind of problem with the USB external drive that I used to copy the music library to the new computer's C drive. It is a 3-terabyte drive with a USB three interface. If that drive is connected to the computer during the boot cycle, it hangs at the end of the splash screen and will NOT finish the boot sequence. If I unplug this drive and re-boot then everything is normal. After the computer is running I can connect the same drive and read it normally. If I then shut down the computer and reboot, it will again hang at the same point in the boot cycle. Whatever is going on with the external drive must have had something to do with the problem I had installing MC18. Obviously, the problem was not with MC.
I rechecked the USB drive and there is nothing on the drive except the music library. The first time I installed MC18, it ran normally for some time, but crashed fairly soon after I copied the library to the new computer. I used copy and paste to load move a copy of the library to the new computer. I then used the "import single folder" to import the music library that was created with MC17 into MC18. After that was when the problem started. Does any of this suggest what the problem might have been? At least everything is okay now. Thanks