My apology for the extended period without reply! Actually, Brian, I still am seeing FixSpeed's popup, and have done nothing about it other than ignore and cancel it each time.
A different issue is now pestering me. Besides my primary computer with Windows 7, I have an HP laptop, about 7 or 8 years old, I think, with Windows XP on it. It apparently became infected with some malware that seemed to be using the laptop for its own purposes. It made the laptop terribly slow, so I "disabled" all of its network connections, and relegated the laptop to serving as a depository for a variety of files I like to keep backed up. With networks disabled, it operated at acceptable speed.
But very recently I set up a wireless connection for my primary system, which had previously been running via a direct cable connection to the Internet. The wireless connection was necessary in order to serve my wife's new Kindle.
Both my primary system and the laptop have DropBox installed. With networks disabled for the laptop, its DropBox was inactive, but suddenly became active when I installed the router for my wife's Kindle! All network connections are still disabled, according to Windows XP, but DropBox activity is ongoing! Moreover, the laptop has become incredibly slow again, and reveals a great deal of HD activity. This has forced me to shut the laptop down. When I try to use it, it takes "forever" to boot up, and the incessant disk activity resumes.
I'm suspecting that "disabled", as reported by Windows XP, is not really true. Perhaps I will have to find and remove the laptop's network adapter. What do you think?