>I have a dedicated Windows 2003 server running IIS 6.0 that was setup a few months ago. When I deploy my code to the web server and run it, I get an error.

Could you see if you have this class ID in you registry:

{88d969c0-f192-11d4-a65f-0040963251e5}

This is the one for Msxml2.DOMDocument.4.0. If it is not there, then it would mean the installation of the component you did on the server didn't work well or was not the proper one for that component.