Microsoft Knowledge Base Article 299451 contains the following summary:

This article describes how to remove and reinstall TCP/IP on a Windows 2000 domain controller.

When you troubleshoot an issue, you may suspect that a TCP/IP-related component is either corrupted or damaged, which may or may not include registry problems. To resolve your difficulties, you may try to remove TCP/IP and all related components, including registry entries, but you may find that you cannot continue because the computer is a Windows 2000 domain controller. The following procedure describes how to remove and reinstall TCP/IP on a Windows 2000 domain controller.

Note: You must consider the following procedure only when all other troubleshooting is unsuccessful in resolving the issue. If you use this procedure, it is strongly recommended that you back up your whole computer. Although this procedure has been successfully implemented on many occasions on other computers, it is possible that in certain circumstances this procedure may cause undesirable effects upon your computer.

Also, Microsoft recommends that you read this whole procedure before you start so that you have a clear understanding of the procedure.