Re: Messages to +owner being wrongly routed to the whole group
... so it confirms the earlier experiments and points to the culpritAnd, following up with a similar case reported by another member I have evidence to implicate synchronoss.net
Off-list Trista sent me the header for a misdirected message that posted into her group. In the following two Received fields note particularly the "for" clauses:
Received: from re-prd-rgout-002.btmx-prd.synchronoss.net ([10.2.54.5])<20190904180319.WRUD7208.email@example.com>
for <firstname.lastname@example.org>; Wed, 4 Sep 2019 19:03:19 +0100(authenticated as [redacted]@btinternet.com)
id 5D6FA3290010097DThe second is synchronoss saying that they received the message from the member's iMac, intended for the +owner address.
The first is btinternet saying that they received the message from synchronoss, intended for the group posting address.
I don't know for a fact about these two services, but I believe that servers generally record in the Received header very literally what they received. Which in this case would imply that synchronoss trimed the "+owner" off of the address after receiving it from the member's iMac and before delivering it to btinternet.
That's what I call a smoking gun.
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