So I created a network using Hamachi, my friend joined, copied my IP from Hamachi, pasted it in direct connect, and I told him the port. He didn't write anything wrong, every number was correct. Even though we did everythnig well, he couldn't join. This is the message he got: failed to connect to the server. io.netty.channel.AbstractChannel(dollar sign)AnnotatedConnectException:Connection refused:no further information What could go wrong?