When my friend trys to connect to the realm he cant seem to connect we see him for a few seconds in game then he leaves. he gets 

Internal Exception: java.io.IOException: An existing connection was forcibly closed by the remote host.

we tried looking online and cant find anything to solve this. when we first started the realm he connected for about an hour or so but after his first log off he was not able to log back in. we tried re inviting him to the realm and nothing. 

we tried creating a new world same issue.

we checked his internet (using ethernet to connect) and he had something like 30mb/s

he even tried turning off his VPN and Fire wall and nothing. (he had them on even when he was  able to play tho)