Tag Archives: failed send

How to read a email bounce back KB10392116

Email Bounce Back Example: This is just one example and bounce backs can vary server to server so keep that in mind while viewing yours.

Delivery has failed to these recipients or distribution lists:

automated reply
Your message wasn’t delivered because of security policies. Microsoft Exchange will not try to redeliver this message for you. Please provide the following diagnostic text to your system administrator.

The following organization rejected your message: mx.siteprotect.com.
Diagnostic information for administrators:

  1. Generating server: server.domain-name.local
  2. do-not-reply-user@anoher-domain-name.com
  3. siteprotect.com #550 5.7.1 <do-not-reply-user@anoher-domain-name.com>:
  4. Recipient address rejected: Invalid recipient ##

Original message headers:

5.  Received: from server.domain-name.local ([]) by server.domain-name.local ([]) with mapi; Thu, 2 Jul 2015 15:00:11 -0400From:        =?Windows-1252?Q?Company_Name=99_Helpdesk?=        <Support@domain-name.com>To: automated reply <do-not-reply-user@anoher-domain-name.com>Date: Thu, 2 Jul 2015 15:00:10 -0400Subject: *** Please do not reply to this Email ***Thread-Topic: *** Please do not reply to this Email ***

  1. The server sending the bounce, so we know where it came from
  2. The email address sent to, to help verify the correctness and destination
  3. Bounce code, see below for common codes
  4. Bounce Reason, what the server reports as going wrong
  5. The server sending the bounce, where did it come from

Common Codes:

421 <domain> Service not available, closing transmission channel
450 Requested mail action not taken: mailbox unavailable (e.g., mailbox busy)
451 Requested action aborted: error in processing
452 Requested action not taken: insufficient system storage
500 The server could not recognize the command due to a syntax error.
501 A syntax error was encountered in command arguments.
502 This command is not implemented.
503 The server has encountered a bad sequence of commands.
504 A command parameter is not implemented.
550 User’s mailbox was unavailable (such as not found)
551 The recipient is not local to the server.
552 The action was aborted due to exceeded storage allocation.
553 The command was aborted because the mailbox name is invalid.
554 The transaction failed for some unstated reason.