Hey, So recently I've been trying to get a FTB server running so that me and a friend can get on to play. but the problem is that my friend can't join the server. when he tries it gives him an error that says something along the lines of "Cannot connect to server: The ip is invalid on local machine or the ip is invalid on remote machine". NOTES: I run a normal vanilla minecraft server and that works great. so the port-forwarding and the ip is correct but something about FTB just doesnt work. Any ideas? Thanks in advance.