I have 2 Macs on my LAN with a Belkin N1 Vision router. 1 Mac is a VPN server (PPTP). Now, when I try to connect to VPN using the LAN IP address of Mac 1, the connection is successful. However, when I use the WAN IP address, it keeps connecting for some time and fails.

This directly points to the issue to Port forwarding. I have forwarded UDP port 1723 for PPTP VPN. However, the connection still fails using the WAN IP.

Some help would be great!