Client: System.Net.IPHostEntry hostInfo = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()); System.Net.IPAddress myIP = hostInfo.AddressList[0]; System.Net.IPEndPoint myEP = new System.Net.IPEndPoint(myIP, 11000); mySocket.Connect(myEP); Server: // Get the host IP info IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName()); // Grab me an IP... IPAddress ipAddress = ipHostInfo.AddressList[0]; // Set the endpoint IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000); // Make a new TCP/IP socket... Socket myListener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); // Bind socket to endpoint... try { myListener.Bind(localEndPoint); myListener.Listen(100);