Hi Jane !!!
I have some contacts at Symantec and for your problem they told me that Symantec has identified an issue with Norton AntiVirus 2004.
So you have to contact Norton Support - the agents will be able to advise you on the issue. Alternatively, you can run LiveUpdate manually via
http://service1.symantec.com/SUPPORT...98082013035306 but they added that it is strongly recommended going through a support agent if you run Windows XP.