Unable to open NAV 2009

I installed norton antivirus 2009 on last sunday: June 7, live updated, full scanned the system. Everythings worked fine and suddenly on June 10, in the morning I started my system and Norton asked me to restart the system, everything was good up to this point, I was able to browse the Internet and able to access my software. After I restarted the system, Windows XP sp2,  Its not showing taskbar, I am not able to browse the Internet and while I start Norton, after few mins, it says It can not start the product with error code : 8504, 4. I don't know what to do???

 

-Bakul 

 

[edit:Changed subject to reflect user issue.]

Message Edited by shannons on 06-11-2009 07:46 PM