LiveUpdate 5.1.1 (18) 2009 problems with Mac OS 10.6.8

I have just purchased Norton Internet Security 4 following a fresh install of Mac OS 10.6.8 on a brand new HD in my Mac Mini Core2Duo and LiveUpdate will not work - "Updating Error, there was an error performing the update".

 

I have been unable to find a solution that works among the myriad of postings on this forum relating to LiveUpdate issues and should be most grateful for any suggestions from Symantec Employees or other clever people as to what I might try.

 

Many thanks.

 

Pilot.