I'm just guessing here but it could simply be something to do with your router.
If you want someone to connect to your computer, you need to use port forwarding otherwise everything will be blocked because your router won't know where to send incoming data.
Firstly you need to know your local IP address. There are better ways to find it, but I simply click on the little flashing computer at the bottom right of my screen
. Then, I click on the settings tab and there it is (circled in red):
Now that you know your local IP you can forward incoming data to that IP in your router configuration section. When I'm testing things I like to use a feature on my router thats called 'virtual server'. Basically this forwards all incoming data to your computer (don't leave this on because hackers love this):
Or, you can use port forwarding and here you just forward the ports that your application uses:
When configuring a client to be
used by someone not connected to your router, the IP you should use is your remote IP which can be found at
http://www.whatismyip.com.
When configuring a client to be
used by someone connected to your router (this includes a client that you want to use on the same computer as your server) the IP you should use is your local IP.
