Problem FTB Inf Evol 2.5 local server not starting

[EspyyX]

I am looking to start a local server for me and a friend, i can play single-player fine, but when i try to create a multiplayer server using the Server Address: Localhost , it creates the server, but never lets me connect. I am using Ethernet and have NEVER had any connection problems, which leads me to think its not a network problem. Please help me!! ( also i have a Beefy computer)

 

[mc.crab]

What do you mean with: using the Server Address: Localhost? If you have localhost or any other ip addres in your server.properties file remove it and leave it blank.