Auto-Submitted:
Why the bounce sendmail
When a message is returned because of an error or
because a return receipt was requested, V8
sendmail adds an Auto-Submitted: header.
This header describes the reason for the
return:
Auto-Submitted: auto-generated (reason) Auto-Submitted: auto-replied (reason) ← V8.12 and later
The reason can be one of
four things. It can be warning-timeout if the message has
reached its Timeout.queuewarn option threshold
(Timeout on page 1097). It can
be postmaster-warning if the failure was
delivered to the postmaster as a result of a problem
that the postmaster should fix, such as an MX
configuration error. It can be return-receipt if the
message was returned because of a Return-Receipt-To:
header (Return-Receipt-To: on
page 1165) or a DSN NOTIFY=SUCCESS request
(RFC1891). Finally, it can be failure for any other
reason.
In all instances, sendmail also
adds a Subject:
header that contains a generic bounce
message.
The Auto-Submitted:
header should never be defined
in the configuration file.
Get sendmail, 4th Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
