How to connect to telnet sever which created in embeded ?

Question

I created a telnet client in c# and one of my colleague made telnet server with embedded program and he starts server from cmd.exe and then "Telnet 192.168.x.x" window appears I just want to connect to this server so that when server passes any value client will capture it and run methods written in client program and give output to telnet server but when we start to connect to both they are not allow to connect why this happens?