Okay, folks, I was able to install the Windows 10 Fall Seeyalater Update, or whatever it's called. The upgrade succeeded only after I completely uninstalled all IObit products. I have reinstalled most of them, and the computer is doing the other thing that has infuriated me since I installed the SSD drive, which is freeze and hang all the time. I have now uninstalled IObit Malware Fighter but have left everything else. If the machine runs smoothly now, great. If it doesn't, I will progressively uninstall IObit programs one at a time to see if that fixes the problem. (sigh) It's a shame; up till now, I have been extremely satisfied with IObit products.