C# port forwarding

I'm developing a simple p2p program that is meant to work over the Internet, this works fine on a LAN, but when a router and internet connection are involved nothing gets to the machine. I am aware that this is a network question more than a C# question, but I can't have users of this program set up port forwarding every time they want to use the software. I have read the other posts regarding this, but most seem old, so I was wondering if VS2010 has any way to tackle this.

Note: The code for the networking is already complete, and uses TCPLsteners and Clients, so开发者_如何学Go I can't switch to any other method...

Thanks,

PM

Is there a UPnP Library for .NET (C# or VB.NET)? looks promising...