By default, TCP/IP forwarding is turned off (disabled) in Windows Server 2003. This article describes how to enable TCP/IP forwarding on a Windows Server 2003-based computer.
Enabling TCP/IP Forwarding
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
Start Registry Editor (Regedit.exe).
Locate and click the following key in the registry: