Friends Disconnect When Zoning

[whiteknight33]

I had made a post in the Linux section last week when I received an error message when connecting from an outside connection. I had thought it was an isolated incident, but tonight I was attempting to play with a friend. He could connect to my server with ease, but every time he went to zone somewhere, the server would crash him out with the following code:

[Error] GetAuth() returned false kicking clientLoginserver:  		
Client disconnected (cs=d): No name

I was hoping that someone could tell me what this means and if there is a way to fix it? It's pretty annoying that he can't zone anywhere without crashing.