Sounds like the same problem I had with a "full" version of Norton I had on a previous computer to which I wanted to install a different protection package. Used the removal tool from Norton, but found that some references were still stored in "Shared File" directory. Check that. Additionally, some free shareware protocols have removal tools that work.. Take a look at "Error Expert" for one, "Perfect Uninstaller" is another.
Additionally, take a look at this site... Best of luck!
http://www.bleepingcomputer.com/forums/lofiver sion/index.php/t34671.html ...