I have a user who is trying to send a message to someone from our Exchange 2003 and is receiving errors. My first impression is that the address he is sending to is invalid. However, it says #5.5.0 smtp; 550 No such user - psmtp. What's the psmtp part about? I tried telneting to sacbee.com on port 25 and didn't get a response. Is there something I should do to my server to correct the problem. I don't seem to be having trouble sending to other addresses.Thanks for your help. The complete error message followsFrom: System AdministratorSent: Monday, October 12, 2009 3:06 PMTo: Frank M. MitloehnerSubject: Underliverable: TestYour mesage did not reach some or all of the intended recipients. Subject: Text Sent: 10/21/2009 3:06 PMThe following recipient(s) could not be reached: EMAIL GONE on 10/12/2009 3:06 PM There was a SMTP communication problem with the recipient's email server. Please contact your system administrator. <JHabersham.ansci.ucdavis.edu #5.5.0 smtp;550 No such user - psmtp>

Is this a newly created user? Was this working for this partcular user?Looks like some kind of Spam filter or some filter server on there side has rejected the email.JHabersham.ansci.ucdavis.edu is the recipient domain (hopefully) which generated the NDR.Raj

The message was sent from JHabersham to sacbee.com. JHabersham is my Exchange 2003 server and the NDR was received on JHabersham. I'm not sure what you mean by "recipient domain" (recipient of the sent message or recipient of the NDR). I just noticed in my post that they replaced the destination email address with "EMAIL GONE". To understand the appearance of the real NDR replace EMAIL GONE with someusername at sacbee.com.What's psmtp?Curt

Do you have some sort of filtering application or device like postini or mail marshall where you need to add the user to some kind of policy.Is this a newly created user and was it working earlier.Raj

The guy that is sending the message has been on my server for a long time. I have Sunbelt Vipre Email Security. From what I can tell, the message is being blocked by the receiving server not my server. Am I wrong? This guy can send mail to other users but recieved this NDR once each from two different users. Strangely, both messages were sent to newspapers. (He told me it was happening a lot and and just now told me it happened twice. I guess twice is a lot for him.)Curt

Cool, so if the user is old one, can send emails to other domains fine, and mails to newspapers are not going in, strong possibility is that your mail systems are fine. some policy on the there (emails systems of newspaper) is blocking email. Probabaly some sort of spam "key words" in there filtering systems.Relax and send a notification to the mail admin on the other side.Raj

Thanks. It does look like they are blocking mail from my server. I tried to send a message to postmaster at sacbee.com and I got the same NDR. I sent the same message from my gmail account and that went through. I'll wait and see if I get a message from the postmaster.Curt