This article describes how to enable Transmission Control Protocol/Internet Protocol (TCP/IP) forwarding on a Windows XP-based computer. By default, TCP/IP forwarding is not enabled in Windows XP.

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To enable TCP/IP forwarding, follow these steps:

1.	Start Registry Editor (Regedit.exe).
2.	In Registry Editor, locate the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
3.	Set the following registry value: Value Name: IPEnableRouter Value type: REG_DWORD Value Data: 1 A value of 1 enables TCP/IP forwarding for all network connections that are installed and used by this computer.
4.	Quit Registry Editor.