On Mon, 30 Oct 2023 10:40:42 +0000, Terry Pinnell wrote:

> I deleted that IMAP account but no change. Still getting duplicates.
> Just sent one to myself. Do the two respective headers help identify the
> cause please?

Look at these...

A. First Look at the "X-Agent-Received:" header line, which is added
by Agent when downloading the email.
1) The first header below was downloaded from Gmail (not from BT).
~~~~~~~~~~~~~~~~~~~~~~~~ QUOTE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
X-Agent-Received: from Gmail (POP) (pop.gmail.com); Mon, 30 Oct 2023 10:01:45 +0000
~~~~~~~~~~~~~~~~~~~~~~~~ QUOTE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2) The second header below was downloaded from BT.
~~~~~~~~~~~~~~~~~~~~~~~~ QUOTE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
X-Agent-Received: from BT (POP) (mail.btinternet.com); Mon, 30 Oct 2023 10:01:45 +0000
~~~~~~~~~~~~~~~~~~~~~~~~ QUOTE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For some reason Gmail is putting a copy of the sent email into
your Gmail POP3 Inbox. This is where Agent gets the first copy
below from.
* Perhaps your iOS mail app is configured to Bcc a copy of the
email to your Gmail account.
* If it is not your own iOS mail app settings, it might be your
Gmail account settings. However, I am not aware of a Gmail
account setting which would do this.

Ultimately it would be settings you control which are putting a
copy of the email into your Gmail inbox in addition to sending
the email to your BT inbox. The headers don't tell me which
settings are doing this, only that this is what is going on.

B. Now look at all the "Received:" header lines in each header.
These, read from bottom to top, show the email hopping from
server to server on its way to the destination.
1) The first header below has no "Received:" header lines.
This means it has not gone anywhere. You posted it from
your Gmail account, and this copy was still in your Gmail
account from where Agent downloaded it.
2) The second header below has these three "Received:" header
lines:
~~~~~~~~~~~~~~~~~~~~~~~~ QUOTE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Received: from re-prd-rgin-014.btmx-prd.synchronoss.net ([10.2.54.22])
by re-prd-fep-014.mx.internal with ESMTP
id <20231030100139.PYSN12241.re-prd-fep-014.mx.internal@re-prd-rgin-014.btmx-prd.synchronoss.net>
for <(my BT mail address)>; Mon, 30 Oct 2023 10:01:39 +0000
Received: from mail-lf1-f47.google.com (209.85.167.47) by re-prd-rgin-014.btmx-prd.synchronoss.net (5.8.818)
id 647E765D1820188E for (my BT mail address); Mon, 30 Oct 2023 10:01:39 +0000
Received: by mail-lf1-f47.google.com with SMTP id 2adb3069b0e04-507c91582fdso6134467e87.2
for <(my BT mail address)>; Mon, 30 Oct 2023 03:01:39 -0700 (PDT)
~~~~~~~~~~~~~~~~~~~~~~~~ QUOTE ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

These header lines must be read from bottom to top.
* The bottom "Received:" header is your email hopping
from one Google server to another, from where it will
then be sent off to BT.
* The middle "Received:" header is your email hopping
from a Google server to a BT mail exchange (mx) server.
* The top "Received:" header is your email hopping from
the BT mail exchange (mx) server to the server where
your BT inbox lives.

______________________________________________________________________

> MIME-Version: 1.0
> Date: Mon, 30 Oct 2023 10:01:28 +0000
> Message-ID:
> <CAEU3o8458DBHKx=nEnfjbNnJmXTZXmi6tC5+454ukebfcfdx5A@mail.gmail.com>
> Subject: From g to b on iPhone
> From: Terry Pinnell <(mygmail address)>
> To: Terry-BT-email <(my BT mail address)>
> Content-Type: multipart/alternative;
> boundary="0000000000002a685c0608ec1f1e"
> X-Agent-Received: from Gmail (POP) (pop.gmail.com); Mon, 30 Oct 2023
> 10:01:45 +0000
> X-Agent-Junk-Probability: 0
>
> ====================
>
> Return-Path: <(mygmail address)>
> Received: from re-prd-rgin-014.btmx-prd.synchronoss.net ([10.2.54.22])
> by re-prd-fep-014.mx.internal with ESMTP
> id
> <20231030100139.PYSN12241.re-prd-fep-014.mx.internal@re-prd-rgin-014.btmx-prd.synchronoss.net>
> for <(my BT mail address)>; Mon, 30 Oct 2023 10:01:39 +0000
> Authentication-Results: btinternet.com;
> dmarc=pass header.from=gmail.com;
> dkim=fail;
> spf=none smtp.helo=mail-lf1-f47.google.com;
> spf=pass smtp.mailfrom=gmail.com;
> bimi=skipped
> X-OWM-SPF-MAILFROM: Pass
> X-OWM-SPF: 0
> Received-SPF: none (re-prd-rgin-014.btmx-prd.synchronoss.net: domain
> mail-lf1-f47.google.com does not designate permitted sender hosts)
> identity=helo; receiver=re-prd-rgin-014.btmx-prd.synchronoss.net;
> client-ip=209.85.167.47; helo=mail-lf1-f47.google.com;
> Received-SPF: pass (re-prd-rgin-014.btmx-prd.synchronoss.net: domain
> gmail.com
> designates 209.85.167.47 as permitted sender) identity=mailfrom;
> receiver=re-prd-rgin-014.btmx-prd.synchronoss.net;
> client-ip=209.85.167.47;
> envelope-from=(mygmail address); helo=mail-lf1-f47.google.com;
> X-Originating-IP: [209.85.167.47]
> X-OWM-Source-IP: 209.85.167.47 (US)
> X-OWM-Env-Sender: (mygmail address)
> X-SNCR-Rigid: 647E765D1820188E
> X-OWM-DMARC: spf 0 dkim 7
> X-OWM-DKIM: 2
> X-VadeSecure-score: verdict=clean score=50/320, class=clean
> X-SNCR-VADESECURE: CLEAN
> X-RazorGate-Vade:
> gggruggvucftvghtrhhoucdtuddrgedvkedruddttddgtdelucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuueftkffvkffujffvgffngfevqffonecuuegrihhlohhuthemuceftddunecugfhmphhthicusghougihucdlhedtmdenucfjughrpegghfffkffuvfgtsegrtderredttdejnecuhfhrohhmpefvvghrrhihucfrihhnnhgvlhhluceothgvrhhrhihpihhnghhmsehgmhgrihhlrdgtohhmqeenucggtffrrghtthgvrhhnpeeitddtheevudeuteeijeeuvdeuteetheetgeehgfejgefftdfhleeludevieetieenucfkphepvddtledrkeehrdduieejrdegjeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhephhgvlhhopehmrghilhdqlhhfuddqfhegjedrghhoohhglhgvrdgtohhmpdhinhgvthepvddtledrkeehrdduieejrdegjedpmhgrihhlfhhrohhmpehtvghrrhihphhinhhgmhesghhmrghilhdrtghomhdpnhgspghrtghpthhtohepuddprhgtphhtthhopehtrdhpihhnnhgvlhhlsegsthhinhhtvghrnhgvthdrtghomhdprhgvvhfkrfepmhgrihhlqdhlfhduqdhfgeejrdhgohhoghhlvgdrtghomhdpshhpfhepphgrshhspdgukhhimhepfhgrihhlpdhgvghokffrpegfufdpoffvtefjohhstheprhgvqdhprhguqdhrghhinhdqtdduge
> X-RazorGate-Vade-Verdict: clean 50
> X-RazorGate-Vade-Classification: clean
> Received: from mail-lf1-f47.google.com (209.85.167.47) by
> re-prd-rgin-014.btmx-prd.synchronoss.net (5.8.818)
> id 647E765D1820188E for (my BT mail address); Mon, 30 Oct 2023
> 10:01:39 +0000
> Received: by mail-lf1-f47.google.com with SMTP id
> 2adb3069b0e04-507c91582fdso6134467e87.2
> for <(my BT mail address)>; Mon, 30 Oct 2023 03:01:39 -0700
> (PDT)
> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
> d=gmail.com; s=20230601; t=1698660099; x=1699264899;
> darn=btinternet.com;
> h=to:subject:message-id:date:from:mime-version:from:to:cc:subject
> :date:message-id:reply-to;
> bh=MJgBuCpOBSnwycoDbV2pkVjPi7Yc7pe/fwjnSg3UY1k=;
> b=W/BxzXVw1mJc9ja6V9H/zq3XVBHTHGurnavr1RIKJ/7ypqxcQoexvsv8cwJmNubArr
> nBQ7uUdAH0/FvbxbC+NYGfiimXRFCJoEOCNF/Uzd8412VnBLXgQzdDyHloLteWgJElEq
> SxjcWbwbSNBRmo2As9Gz1XgTAg+LzKFB9BRvEgVvl/mape7WRh0JLSQiXxxgHCIu5EZo
> 7B1C00WoULV/q/A07LPM5fgkEChzd6F1eWHAiALTKd8QB51Oa8GxEDnpb+0ONSWYmx8z
> xREldzaT6IqXfXKu5zzAC3ZpTbpI2agUR5D1VabuWTpD+TvraKDr9ksrERlPtWzPnyDN
> IvDw==
> X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
> d=1e100.net; s=20230601; t=1698660099; x=1699264899;
> h=to:subject:message-id:date:from:mime-version:x-gm-message-state
> :from:to:cc:subject:date:message-id:reply-to;
> bh=MJgBuCpOBSnwycoDbV2pkVjPi7Yc7pe/fwjnSg3UY1k=;
> b=ZcMurd8iYEkNtrXwdpCtC5HeoQgjjOm/MsjWbxHCN/3975Jfip3eYcVtvXUApJHE0R
> 1hIpUEQnclw/qAdBqq7OvHnZZD3U48hodz2Yzsj/J6CoipmsmbD4+C6h5S/x5QkzXbkC
> kmfvtAfLe1FDGxsk6YzyQxPrfPA80DFutgQ30NRUA+PMzIrJbPP1HG1O9W9rEmneYM2j
> EiJ6BOKTNZaeKSBSNwdjqwhi+mw4Vd9esiBIMLiQZ+h53L/qkEa2jmd3H07S8GVYV0Jd
> IPDhF8mWyVUTjK0L7plBzapnx7ZzvgJg6pTApJjCgIdsLZjhnNV7Zj6D8s2R1+d+c5E5
> FXzg==
> X-Gm-Message-State:
> AOJu0YxoM2X7Y3mJEtXI3bmBPpbCm23HrwjGZSefXT6AKXdnSqKnfJ+0
> loV3VLAl5XkuVGlITtmigqj1PO6jFeG31qfGMP1yNC2+024=
> X-Google-Smtp-Source:
> AGHT+IETiggGaDcr1amq1L9EAv286pKA9CFP0jrkOITzmxFBJHQqqF7a0hFTetDG37iUJxQGEOH+8UEpBdzfnkcNR/w=
> X-Received: by 2002:ac2:5183:0:b0:509:1301:8470 with SMTP id
> u3-20020ac25183000000b0050913018470mr3030416lfi.45.1698660098938; Mon,
> 30 Oct
> 2023 03:01:38 -0700 (PDT)
> MIME-Version: 1.0
> From: Terry Pinnell <(mygmail address)>
> Date: Mon, 30 Oct 2023 10:01:28 +0000
> Message-ID:
> <CAEU3o8458DBHKx=nEnfjbNnJmXTZXmi6tC5+454ukebfcfdx5A@mail.gmail.com>
> Subject: From g to b on iPhone
> To: Terry-BT-email <(my BT mail address)>
> Content-Type: multipart/alternative;
> boundary="000000000000caa0730608ec1fe2"
> X-Agent-Received: from BT (POP) (mail.btinternet.com); Mon, 30 Oct 2023
> 10:01:45 +0000
> X-Agent-Junk-Probability: 0

--
Regards
Ralph Fox

“The power of accurate observation is commonly called cynicism by
those who have not got it.” — George Bernard Shaw