Connecting to pop3 and postfix

I have just put 8.2 on a Dell Optiplex. Finally got two NICs running having had to disable internal one. Created a user account with password. Set up Samba. Can connect from w2k box to samba shares but pop3 and smtp from Pegasus just won't connect. /var/log/messages shows the pop3 service responding but it keeps saying Logout user=???. Postfix claims to be running (tried a start and it complained it was there) On smtp the pegasus just says it cannot connect. I had got used to sendmail