TCP / IP Forwarding for Windows XP
Always backup your System Registry before making changes to your registry. How to Backup your Registry.
Clip from Microsoft KB: KB 315236
(If setting up OpenVPN)
To enable TCP/IP forwarding, follow these steps:
1. Start Registry Editor (Regedit.exe).
2. In Registry Editor, locate the following registry key:
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.