List of ports required for the game:
TCP 80, 443, 3800-3815
UDP 35000-36000
Required ports for the launcher:
TCP 27022-27042, 6881, 8090
For connection related problems use the Connection Tester. You can find it in your Game folder. Star Conflict\con_tester
Using Steam? You can find it in the installation path of Steam. Mostly C:\Programms\Steam\steamapps\common\Star Conflict\con_tester