Hello,

I apologize that I'm useing english, but in german my grammar not the best yet.

So I wanted to activate a port for my server ( for example now for Minecraft). At the first time (about 2 years ago) I had succes with a port opening (router type was Speedport Smart with Tarif M) but after a time my friends couldn't join to my server. I looked after the issue and port was closed without any info. Only one thing was changed is a yellow square with a exclamation mark in it.

Since then I can't open any port.

We changed the Tarif (because other reason) with new router(Speedport Smart 4 also I reinstalled my PC a few days ago) but that yellow square is still there and I can't open any port too.

Could somebody tell me wht can cause this issue?

Thanks in advance