backscatter / ndr / smtp auth issues

Gavin Silver GSilver at
Mon Feb 22 15:59:42 GMT 2010

Hey all,

Pulling my hair out over this. All of a sudden I am getting what looks like NDRs filling up my mail queue here is an example

Reporting-MTA: dns;
X-Postfix-Queue-ID: D882A4003DC
X-Postfix-Sender: rfc822; laiaduye4777 at
Arrival-Date: Mon, 22 Feb 2010 09:43:14 -0500 (EST)

Final-Recipient: rfc822; UNKNOWN_USER at
Original-Recipient: rfc822;UNKNOWN_USER at
Action: failed
Status: 5.1.1
Remote-MTA: dns;
Diagnostic-Code: smtp; 550 5.1.1 User unknown


MAILER-DAEMON at (Mail Delivery System)


laiaduye4777 at


Mon, 22 Feb 2010 09:43:52 -0500 (EST)


Undelivered Mail Returned to Sender

This is the mail system at

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

< UNKNOWN_USER at >: host[client.server.ip.address] said: 550 5.1.1 User
    unknown (in reply to RCPT TO command)

My mailscanner is running in a gateway setup for multiple domains on ubuntu 8.04LTS / postfix
Mailscanenr version is 4.58.9 (*duck* I know! Im going to migrate everyone to a brand new updated version on centos very shortly.. :-/ )

I have smtp auth enabled in postfix according to documentation found on so im not sure why my gateway is even sending bounces

Gavin Silver

-------------- next part --------------
An HTML attachment was scrubbed...

More information about the MailScanner mailing list