I have windows xp sp2, and im trying to make a VPN server in it. I followed the basic steps (Control panel> Set up a new conection > Setup advanced connection > etc.. etc..), i also port forwarded both ports PPTP and L2TP in my modem (3com 3CRWDR101A-75). Also im not trying to set it up for a local network, my goal is to get another computer to connect to my VPN so this computer will have the same [b]PUBLIC[/b] IP address as mine. Again, this other computer is not part of my local network. Also please can anyone confirm that a computer that connects to my VPN through my public IP address, will it start having my public IP address aswell ? So my VPN would also work similar to a proxy... AFter the VPN server is set up , i right click on its icon, then Network > TCP/IP Properties> and i tried both options there, either automatically assign TCP/IP address using DHP, or specifying the adress myself. When i specify them myself, as im not setting it up for local network, i just put my public IP address. Like i said i tried both options, but none works, when my friend tries to connect using my public IP address, correct login and password, he gets Error 800 - COuld not stabilish a connection. I tried other settings on the VPN server properties, but there isnt much to change, very few options. I think its something related to the modem, but dont know what... I tried disabling NAT, but then i can teven connect to the internet. If anyone has any idea please let me know and i'll see if it works Thanks

No 2 computers can have the same IP address. When you set up your port forwarding, make sure that the source port is "any".

But then theres no way todo what i want ? What if i created a proxy server on my PC ? Or do the reverse proxy thing ? Do you mean the protocol type ? i set it to tcp/udp Thanks

I really don't have a clear understanding on your goal. You can create a VPN from one machine to another using VPN software & port forwarding on the router. What else are you trying to do?