I have a server on one of the several PCs in my home. When I run it, my friends can connect just fine. If someone in my house hold gets on on the other hand, they are on for at most 3 minutes before they get kicked and then no matter what PC or Laptop you try to use we can't get back on unless the whole server gets rebooted. In the mean time all of our friends are untouched. It is just anyone trying to get on at home that is having the issue
The error that shows up on my laptop and any other home pc are:
External ip - "Connection refused: No further information"
Internal ip - "Authentication servers are down. Please try again later, sorry!"
On the actual server list it then shows "Can't connect to server"