Hello all, First and foremost, thanks to those who continually answer on this list! I think a server is misconfigured, however the higher ups say no, so I figured I would ask the experts here. Server: MS Exchange 6.5 Fails on sending to Exim servers, everything gets bounced. This is what Yahoo sees in the headers, Received: from 65.121.44.80 (EHLO dnmssmtp1.ec.cf.com) (65.121.44.80) by mta334.mail.mud.yahoo.com with SMTP; Mon, 18 Sep 2006 14:17:45 -0700 Received: from EXMAIL2.ec.cf.com ([10.15.132.141]) by dnmssmtp1.ec.cf.com with Microsoft SMTPSVC(6.0.3790.2499); Mon, 18 Sep 2006 15:17:42 -0600 The mail states it is from username@xxxxxxxxx Yahoo accepts the email, Exim does not. One other is mail is at imss.gates.com You can telnet to imss.gates.com 25 and do the testing. telnet gates.com 25 fails any ideas? John A Oligario