Unexpected Reply-To in sent email

Mail
1

Hi, I’m a long-time user of eM Client and I love it - it’s by far the best email client on the market.
However, I am having a small issue when using eM Client 9.2.2258 (7080479).

When I send an email through an Exchange Web Services account using an aliased email, even if I confirm that the alias should be used as the Reply-To address through Mail > Reply to address > Custom, the canonical email is set in the Reply-To header and the notification header…

Enclosed are the headers of the email sitting in my Sent folder after sending.
I have masked the emails in the header, where my canonical email address is email@redacted, and the alias is alias@redacted.

From: "Alias" <alias@redacted>
To: "Test" <[email protected]>
Subject: replyto test
Date: Sat, 15 Jun 2024 19:18:52 +0000
Message-Id: <redacted>
Reply-To: "Email" <email@redacted>
Disposition-Notification-To: "Email" <email@redacted>
User-Agent: eM_Client/9.2.2258.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline

However, when I send a similar email from an IMAP/SMTP configured account, (in this case it is an iCloud account) it is set as expected:

From: "Alias" <alias@redacted>
To: "Test" <[email protected]>
Subject: reply-to-test-4
Date: Sat, 15 Jun 2024 19:19:43 +0000
Message-Id: <redacted>
Reply-To: "Alias" <alias@redacted>
Disposition-Notification-To: "Alias" <alias@redacted>
User-Agent: eM_Client/9.2.2258.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: quoted-printable

I have already checked that alias@redacted is a registered email for the account in Exchange.
Is there anything else I can check in my mail server configuration? I don’t have any Mail Flow rules which modify the headers.

Is it possible that this is an issue on the eM Client side?

2

I’ve just tried this in eM Client 10 and I’m still experiencing this issue.

From: "Alias" <alias@redacted>
To: "Test" <[email protected]>
Subject: replyto test
Date: Mon, 09 Sep 2024 20:00:08 +0000
Message-Id: <redacted>
Reply-To: "Email" <email@redacted>
Disposition-Notification-To: "Email" <email@redacted>
User-Agent: eM_Client/10.0.3530.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline
3

I am delighted to say that the error no longer occurs for the saved Sent email in eM Client 10.1.4588;

From: "Alias" <alias@redacted>
To: "Test" <[email protected]>
Subject: Test 20250210
Date: Mon, 10 Feb 2025 17:02:51 +0000
Message-Id: <redacted>
Reply-To: "Alias" <alias@redacted>
Disposition-Notification-To: "Alias" <alias@redacted>
User-Agent: eM_Client/10.1.4588.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline

However on the receiving end, (in GMail) I see this, and the email is flagged for spam:

Return-Path: <alias@redacted>

From: "Alias" <alias@redacted>
To: "Test" <[email protected]>
Subject: Test 20250210
Thread-Topic: Test 20250210
Thread-Index: AQHbe92esYiZgRmJoUKBxwtISx2cpg==
Disposition-Notification-To: "Email" <email@redacted>
Return-Receipt-To: <email@redacted>
Date: Mon, 10 Feb 2025 17:02:51 +0000
Message-ID: <redacted>
Reply-To: "Email" <email@redacted>

So there must be something happening on the Exchange side…