I cant log in into my own server in the snapshot but my friend can

Put the summary of the bug you're having here

so I tried logging into my server after upgrading to the snap shot and I thought that both me and my friend were able to go in.

*What actually happened was that my friend could log in and I couldnt

Steps to Reproduce:
1. get a server up and running on a full relese on you're computer
2.upgrade to the snap shot
3.give a friend the IP and both of you try to log in, it is very importante that you will try to log in from the same computer as the server is running on
if you're friend can and you can't you made it