I am having a problem with WMI.  IT Assistant is able to grab system information from one of my Dell Optiplexes and not another.  I can't figure out what is causing it to work on one system and not on another.  Both systems have firewalls off.  For the most part they are just basic installs of Windows XP sp2.  I'v checked the services on both computers and WMI is running along with the RPC service.  Does anybody know why this would be happening?