I have an app for Microsoft Surface to receive data from desktop application. It works fine if the app runs on my laptop with Windows 8.1 system. But when it's started on my Microsoft Surface it doesn not reveive any messages. I can reproduce this with the DatagramSocker for JS example by Microsoft (http://code.msdn.microsoft.com/windowsapps/DatagramSocket-sample-76a7d82b). The app receives message from it's own connection but not from my desktop PC.
I also checked Firewall settings. I have no idea.