ThomasCarterUK

Your explanations are perfect and have helped a lot. I will attempt the first idea and will report any issues I encounter. Thanks!

That is correct. I want to make it so that messages can only be sent to a specific user.

I have fixed my first issue. For broadcasting messages the server is creating a network stream to every connected IP and is writing the text to that stream.

Yes, I did allow the program through the firewall but still nothing. Originally for the contact system I create an ArrayList. Every time a client connects to the server their username was added to the ArrayList. When they disconnected their name was removed. However the server would no longer broadcast messages. The server already stores connected IPs to a Hashtable. I thought about using this list but I could not figure out how to get the username from the IP.

I am working on a TCP Messenger in Visual Basic. I have created a client and server which uses TCP Clients and Listeners to send and receive messages. The client and server will successfully communicate over the local area network, however the client cannot communicate with the server if the server is hosted on a different network. I have forwarded the port (45576) but the client can still not connect. I checked the port using http://www.yougetsignal.com/tools/open-ports/ and the port is closed. I'm guessing this means the server isn't listening on the public IP just the local IP. I would like the client to be able to communicate with the server over the Internet / Public IP. I would also like help in creating a contact system. The client will be able to see who is online and will be able to send private messages to specific users (Like Skype). I have tried to create a system but the server would no longer broadcast messages so I reverted the changes. I have attached both the server and client source code to this post. My skype is thomascarteruk91 if anyone would like to speak to me there. Thanks Nossic IM.zip