First step; backup any user files that you have created in the program.
Second; properly uninstall the program by either using its uninstall or remove option in the Programs menu OR using Add/Remove programs in the Control Panel. When finished, restart your computer (Start --> Shut Down, Restart)
Next, reinstall the program with one small change: When the setup screen comes to the destination directory (something like:
C:\Program Files\Netscape\ ), delete one of the back slashes and Program Files. This way you install the program into a completely different directory than before.
Lastly, restart your computer again and restore your backed up information.
Using this technique should help eliminate problems you have with a particular application. I have used this technique successfully with programs like Netscape Communicator, AOL, and Quicken.
Links:
[1] https://www.paypal.com/cgi-bin/webscr?cmd=_xclick&business=rick@yourpcpartner.com&item_name=Buy
[2] http://www.helpmerick.com/node/90
[3] http://www.helpmerick.com/node/88