Norton Antivirus 2005 hangs at startup

Hello,

Me having windows XP professional with SP1 and I am facing an problem with Norton.
I am having Norton Antivirus 2005 and whenever I start my PC with the internet cable/Pin into my PC, the IE and Norton gets Hang-ups for Two Minutes and the Norton icon in the Taskbar gets an Red “X” icon, then everythings get back to normal after a couple of minutes.

This hang problem only happens with IE and Norton, rest all my PC works great.

If I have not inserted the internet pin into my computer Norton and IE starts normal.

Any ideas what is causing this problem?

I have tried:
Re-instaling Norton
Re-instaling XP
Disable/Enable Auto-protect

All the above procedure failed to resolve the issue.

NOTE:
I am not having any kind of third party Firewall on my PC
I am not having more than one Antivirus Software on my Machine
I DONT WANT TO CHANGE MY AV SOFTWARE !!