NPF is a pain in the A## sometimes. Its almost impossible to get good uninstall, and most problems glitchs require just what you tried: un and reinstall.
What you need to do is do ann uninstal from the program group or control panel, then go into the c:\program files and delete the norton internet security files folder, and the live update folder. Then goto run\regedit hk_current_user |software |symantic and right click on and delete that synmantic folder. Then goto run\regedit hk_local_machine | software and delete the symantic folder there. Then you should get a good reinstall which you need because you will never know what else is broken.