On 1 Jan 2018, at 10:33 (-0500), David Jones wrote:
On 01/01/2018 09:29 AM, Bill Cole wrote:
On 1 Jan 2018, at 9:59 (-0500), David Jones wrote:
I think some mail systems will keep the same message-ID per email
thread so your system must reject some replies.
I have not seen such behavior in the past 20 years...
Ok. I stand corrected then. What about bounces? Don't they
intentionally keep all of the same headers with an empty
envelope-from?
Nope. A modern standard 'bounce' message is a MIME entity with a special
type, denoted by a header somewhat like this:
Content-Type: multipart/report; report-type=delivery-status;
boundary="blah.foo.bar-baz/example.com"
It should have a unique MID, a Date header reflecting the time of the
bounce, a Subject header like "Undelivered Mail Returned to Sender", a
To header with the original message's envelope sender, a From header
clearly identifying the last MTA to hold the message and it's non-human
nature such as 'mailer-dae...@example.com (Mail Delivery System)', and
Received headers only reflecting the transit from that MTA to the target
of the bounce.
One PART of a bounce is a message/rfc822 entity which has at least the
headers of the original message and usually some or all of the body
--
Bill Cole
b...@scconsult.com or billc...@apache.org
(AKA @grumpybozo and many *@billmail.scconsult.com addresses)
Currently Seeking Steady Work: https://linkedin.com/in/billcole
