C9 Error - Cant get it fixed

Hello,
i have the C9 erro problem with my server,
here what i've done so far :
-Port Forwarding with Port 15779,15881-15885,15778 and 32000
-My Pc get all time the same ipv4 adress
-Changed the IP in cert and servervfg to the local ip (192.168.xx.xx)
-Set up No-IP and changed the ip in my client

I can conncet to login Server but then the C9 error appears -.-
Local connect throught my local ip works fine.
Somone have an idear what is missing or wrong ?

these ports should be opened - 15779, 15881, 15884

They are open