Try downloading a program called HiJackThis from TrendMicro. If you run it, it won’t change anything on your system at first; it just gives you a list of a lot of programs and utilities that are installed on your system that you might not be able to see otherwise.
Run that scan, and then in the results, look for entries that start with “BHO”. If any of them say XFinity, or Comcast, or something like that, check the box next to them and press the “Remove Selected” button at the bottom.
HijackThis is used primarily for diagnosis of browser hijacking, as uninformed use of its removal facilities can cause significant software damage to a computer. HijackThis does not remove or detect spyware; it lists most common locations where browser hijacking activity can occur.
Thanks for the tip, I may try it when my more informed son comes over.