try searching the registry for any references to the program, any you find delete, then reinstall program.
warning edit registry with caution.
click on start then run and type regedit then export a copy of your registry to your desktop from the file menu.
now click on edit then find type in the name of your program search will begin, hitting f3 will find next instance of what you typed in.
would also suggest you create a system restore point.
do this from programs accessories system tools system restore name it something like b4screensaver problem, that way you can restore system to what it was before you edited registry