While installing our antique Clifford Phonics game on our newish Windows 7 netbook, I made a mistake which required me to reboot the netbook before the installation was complete. As a result, the installed program wouldn't run, but more maddenly the uninstaller didn't seem to do anything. It detected that the program was present and offered to uninstall it, but after the uninstaller ran for a while and declared victory the program was still present and the installer just went to the uninstaller. The solution was found on several websites; it was to go to the registry editor and find the install key for the program and wipe it out directly. The files were still on my hard drive, but the program no longer appeared on the list of installed programs and now the installer worked again and I was finally able to let it run all the way to its finish and the program now works.
Here is the best link on how to do this, followed by the same information not presented as nicely in other links:
https://turbofuture.com/computers/How-to-force-uninstall-a-program
https://www.cnet.com/forums/discussions/how-to-delete-a-program-that-won-t-uninstall-264878/
http://www.techradar.com/news/software/10-tips-for-removing-a-program-that-won-t-uninstall-907471
