Can't join on my Server friend gets error message: connection reset by peer

[Ebrithil_7]

So my friends and I were playing ,on a modded server I created, for about two months now.

But one day no one was able to join anymore. We tried to reinstall hamachi and even reinstalled minecraft. Nothing changed. I don't know what to do anymore. I read that the "reset by peer" error has something to do with the TCP/IP protocol and that I should try to reset my router. That didn't help either.

Here are the server-log and the crash-report.

 

Thanks for your help,

 

Ebrithil_7

crash-2018-12-09_19.32.23-server.txt

2018-12-09-3.log

[Ebrithil_7]

My friend who's not in my network (we use Hamachi) is getting the reset by peer error.

I get "java.lang.NullPointerException: group