I am writing a C# console application for Windows 7 that can send and listen to packets (client or server). Since I only have one computer, I will have to debug and test my code locally.
I first created a new rule in Windows Firewall with Advanced Security, given it a name "Foo" and enable a TCP port of "55000".
I then install telnet on my command prompt. I tried
open 127.0.0.1 55000 open localhost 55000 open 192.168.1.122 55000 // my local network IP
Could not open connection to the host, on port 55000: Connect failed.