Method=8

Hello,

I am wondering if any one here can tell me what method=8 as an authentication type means. I am getting failures form a user and don't quite understand how they set up their email program. Following is what I am getting...

173.31.xx.xx [39D4] 10:36:21 Authentication [POP3] - Result=0, User=, Method=8

Just looking for help on setting the user up correctly.