Problems With My Ports... Or Maybe Network Id?

[SIDESTRE4M]

Ok, before someone will post the link to what to do when multiple clients try to use the same internet connection, utilizing different ports... I know that, I've done that and it worked.

 

Now, I'm not able to play with my friend together anymore, when he visits me. The systems didn't change, neither did the settings, neither did the router settings.

 

Did you guys change server settings regarding network ID oder something?

 

EDIT: I might add something: Both systems show me "All systems nominal" but when we join a game together, one gets kicked out.

Edited March 30, 2014 by SIDESTRE4M