When I saw an error message come up for NAV11, I decided to reinstall it from my original Norton disk. After installation and restarting the computer, I can't open NAV anymore, and an NAV error pop-up (ERROR 10) appears every ten seconds or so. I can't get rid of the pop-up, either by restarting the computer or by reinstalling NAV from the original disk. This pop-up has essentially hijacked the computer, since I have to click on it every ten seconds to get rid of it. Any suggestions?