Vista user permisssion problem

this is my first ever post, and I am an average user, so please be patient. I
have a problem with NIS2008 and Vista HB. Norton has worked on the problem
and reports it is a windows issue. I have 2 user accounts. One admin and one
standard user. Norton comes up and runs live update for the administrator.
But it will not update for the standard user. i am told this is a permissions
problem. When it tries to update the standard user the admin permisssion
window comes up. and even though I follow all the instructions (enter my
password) it does not allow me to run the live update for the standard user.
This problem did not exist using NIS 2007. I have loaded all the vista
updates as they are available. I loaded this on my other machine running
Vista Premium with no problems at all. I would really appreciate some
guidance.