NIS 2009 on Vista x64 with SP2. Scheduled scan does not run if different user is logged on

I just built a brand new PC and installed Vista x64 + SP2 on it.

 

Installed  NIS 2009 + all live update patches.

 

I have 2 user accounts on the PC - AdminUser and PCUser. AdminUser is the first admin account that Vista creates. PCUseraccount is a regular "user" account in Vista.

 

I used the AdminUser account to install and configure all software including NIS. Created a scheduled full-system scan to run daily using this account. This account is only used for software installation when needed.

 

PCUser account is what is used by default on the PC. That is the user account that is always logged in.

 

NIS scheduled scan does not run if PCUser account is logged in at the scheduled time. It runs successfully if the AdminUser account is logged in at the scheduled time.

 

I logged in as the AdminUser, went to Vista's Scheduled Tasks list and changed the properties of the NIS scan task to "run even if the user is not logged in". It still does not work ifPCUser is logged in at the scheduled time.

 

In NIS, if I change the user account for the scheduled scan to PCUser, it runs fine when the PCUser is logged in. However, the PCUser account does not have adequate privileges to scan system folders and clean up protected areas. 

 

So, I would like to run the Scheduled Scan task using the AdminUser account even when PCUser is logged in to the PC. Any suggestions on how I can achieve this?

 

Thanks in anticipation! If the above description is murky, please let me know and I will try to provide more clarity.

-MediocreFred.