Intranet site going to old IP address

We have recently changed our IP numbering configuation and now our intranet site keeping looking for the old IP address. We have gone into the server (Proliant CL1850) Windows 2000 and have changed all the IP addresses we could find and when we do the IPCONFIG /ALL the IP addresses are correct. The individual that set up this server is no longer with our company and has not responded to our inquiries. Where else can we look so that our intranet isn’t looking at the wrong IP address. FYI: The internet works.