Hi, Papa1.
If you have an OEM version of Office 2003 that came with your desktop PC,
then you probably aren't licensed to install it on a different computer than
the one the software came with. Read your End User License Agreement to make
sure. Microsoft doesn't provide replacement product keys for OEM software.
You should contact the computer manufacturer for a new product key.
If you have a retail version of Office 2003 that you purchased separately
from the computer, then see
http://support.microsoft.com/?kbid=823570 "How to
obtain a new product key for Office program setup".