Migrating a Webservice

We had a webservice client developed for us and it works great on our old Windows 2K server within our old domain. We are wanting to move it to our new Windows 2K3 server within our new domain. When we copy the webservice folder to our new server and change any and all url links on the webservice files and pages, it works great. The problem occurs when we go to delete the webservice folder on our old server, it no longer works on the new server. We have thoroughly checked each file and page within the webservice folder to make sure none of the pages and files make any reference to the old domain name or server. Is there a line within the solution itself that is still referencing the old url/server that has to be changed also? Something is still referencing the old server or url and we can not figure it out. We would appreciate any guidance because we cannot get in contact with the developer. We would offer more points if we could. Thanks in advance!