If you know what portforwarding is, I activated it for the port i used for mindustry (I think it was 8080?).
But I had a function turned on, that blocked a section of ports, after i deactivated it, everything worked fine for me.
Fixed it, I had to deactivate something on my router.
I tried to play with a friend, but couldn't connect to him, even after one hour of trying we could not figure out whats wrong. Could there be a bug that prevents you from connecting to others?