Can't play on realms

Hello, I've a problem with realms. I can connect to my friends realm, but after 15 or so seconds it kicks me out and has the error message:  "java.io.ioexception: an existing connection was forcibly closed by the remote host"

I've tried reinstalling the game, connecting on ethernet and/or wifi, setting an exception in the Windows Firewall, enabling the operating system's restricted environment in the Java control panel.

I don't know what else to do and i really want to play with my friends.