Minecraft multiplayer hexxit?

I want to play minecraft with some friends, but if I'm on the serverlist, it says 'Communication Error' you know what?
PS: If I click on it says, Java.net.SocketException: Protocol Family invaible '

"Communication Error" means that jz, for example, could communicate your Minecraft version with the server. This is mostly because either the modpack was not properly installed on the server, you even use the modpack of another launcher or the server is not strong enough to maintain communication.

Therefore I would recommend you to reinstall the modpack on the server and check if you play with the right modpack. In addition, I can recommend you as a server that endures this and is free, Aternos: https://aternos.org/...os.org/en/