I believe that one is not able to access their own internet address from inside the network. I have to use a web proxy to access mine.
That shouldn't a problem, because you're just sending to an address that gets forwarded by the router to a particular computer in the network. You will have to set your router so that the port that your software uses gets directed to the right computer. On a linksys router, that involves typing "192.168.1.1" into the browser, and then going to advanced options/ forwarding. Check the manual for what port the software is on (e.g., 5500, etc.) and make sure you enter the correct IP address for the server.
original here.