RESTART REQUIRED - never ending NAV 2009 pop up message loop

Any help out there?,  I am running Norton Antivirus 2009 in a windows XP (SP2) machine.  I keep getting a Norton Antivirus Pop Up window saying

 

"RESTART REQUIRED - your computer must restart in order to continue the removal of Security Risks. Restart Required"

 

I then offers options of RESTART NOW (Reccomended), REMIND IN AN 1 HOUR, 12 HOUR, 24 HOUR

 

When I choose retart now, it does, but within seconds the pop up appears again (and again, and again....)

 

Any ideas why or how to stop this nightmarish loop I am stuck in?

 

Advance thanks