Outlook can't be started up in Terminal Server

Hi there,
My outlook 2003 can't be strated up when our terminal server user logs into
the server. THere is an error shown that " Cannot start Microsft Outlook. The
program is not registered properly. Please run set up again." I'm trying to
reinstall MS office and re-activated the product again but it still doesn't
work. However, if I log in on the terminal server by using administrator
account or any authorized user as administrator, there is no problem at all.
I can't find the reason why????
Is there anyone being able to help me to sort this out?