Can you help me with an error problem: Error: LU6004;?

I've had Norton Internet security 2008, on my computer for about six months now and have 72 more
days before it runs out. I've had no problems up until now.

Ok, the problem is that my liveUpdte keeps failing. This is what comes up. Error: ''LU6004: LiveUpdate did not complete successfully.
Every thing was ok, up untill a few days ago. Ican't run any kind of scan at all. Maybe this is due to virus infection on my computer, i'm not sure.

I,m using Windows Vista on my home computer.

Can anyone please help me with this problem?

Thank you. Terry.