SUSE POP3 err unknown authorization command
 

I have installed SUSE ver 9.0 and am trying to build a e-mail server for our organization. We have been running Redhat version 5.1 e-mail server since 1999. Finally quit.
Our unix specialist retired 4 years ago, I mess with Linux as a hobby and have been assigned to create this new e-mail server.
I used Yast to configure sendmail and Qpopper and was really getting frustrated until I found the NIC card had failed. Replace that and it seemed to work. Brought down and some minor changes made and now it doesn't allow signon to the server. You can connect to the server but not signon to receive your mail at your workstation. Outlook appears to be configured properly. It returns the error log onto mail server (pop3):unable to logon to the incoming mail server(pop3). verify user name password and e-mail fields.
telnet to mailhost 110
returns OK send mail .......
user johns
returns err authorization error .......

It appears in my humble opinion to be failing on the user name. Any pointers? files to check?