Hello, I use ispconfig multiserver conf with one webserver and one mail server I set up email addresses and a website (Dolibarr) Here my usecase : From dolibarr, you can send invoice by email. It is using one email authentification and allow you to modify the sender. This gives that king of email : see below for full details As you can see: "Authenticated sender" is different from "From". (Authenticated sender: [email protected]) From: <[email protected]> My understanding is that could be a big reason to be classified as SPAM. Do you confirm ? Digging a bit Dolibarr, they are talking about "Relay" configuration. Could you help me understand what is Relay, how I can build it with ispconfig ? Will it help to avoid SPAM classification ? Code: Return-Path: <[email protected]> Delivered-To: [email protected] Received: from mail1.mydom.fr by mail1.mydom.fr with LMTP id DSr3AfgbdfQ2L2liwAFl6CoA (envelope-from <[email protected]>) for <[email protected]>; Tue, 29 Mar 2022 16:03:11 +0200 Received: from localhost (localhost [127.0.0.1]) by mail1.mydom.fr (Postfix) with ESMTP id F0DFAB02EE6 for <[email protected]>; Tue, 29 Mar 2022 16:03:10 +0200 (CEST) Authentication-Results: mail1.mydom.fr (amavisd-new); dkim=pass (2048-bit key) reason="pass (just generated, assumed good)" header.d=mydom.fr DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mydom.fr; h= content-transfer-encoding:content-type:content-type:mime-version :x-mailer:reply-to:references:message-id:date:date:subject :subject:from:from; s=mydom; t=1648562588; x=1650376989; bh=NfCLv Uyqkohxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx0=; b=fMeZViFEvpGEV61/vNbVV 1iAhgxpNK+Ck0iQKUKv0sthywopekafwbSqLpToeen3JYfycVmV/nlzxJClWAPyj wTSAb9lVcLT0aaVTTTTTTTTTTTTTTTTTTTTTTTTTTTTz2It3WgXC3w03/SW9p9fA EPZbncdCo7iBOzUOywvXaSN5iys88vvkkfZP3JzsGSgY3zW9WbrpUk7XPaW3R2OZ Z/jhCdNHRZ+oN8UY0000000000000000000xW1pWlC5KR+DHVD+XUWmoW3hBXJZ3 +sQ7u2foZtB9zoaKo12lqwKEbkqRD7GSo48vYGdO7LaO4zBzT8OWhrw/PMLqlYR6 w== X-Virus-Scanned: Debian amavisd-new at mail1.mydom.fr Received: from mail1.mydom.fr ([127.0.0.1]) by localhost (mail1.mydom.fr [127.0.0.1]) (amavisd-new, port 10026) with LMTP id pQgRasVmHcmn for <[email protected]>; Tue, 29 Mar 2022 16:03:08 +0200 (CEST) Received: from mail1.mydom.fr (mail1.mydom.fr [161.97.133.21]) (Authenticated sender: [email protected]) by mail1.mydom.fr (Postfix) with ESMTPSA id A0222B00DE1 for <[email protected]>; Tue, 29 Mar 2022 16:03:08 +0200 (CEST) From: <[email protected]> To: [email protected] Subject: Test Date: Tue, 29 Mar 2022 16:03:08 +0200 Message-ID: <1648562588.SMTPs-dolibarr-emailingtest@e29b79274fa64207a218c6c6a2ac36ce> References: <1648562588.SMTPs-dolibarr-emailingtest@e29b79274fa64207a218c6c6a2ac36ce> X-Dolibarr-TRACKID: emailingtest@e29b79274fa64207a218c6c6a2ac36ce X-RemoteAddr: 90.80.40.225 Errors-To: <[email protected]> Reply-To: <[email protected]> X-Mailer: Dolibarr version 14.0.4 (using SMTPs Mailer) X-Dolibarr-Option: MAIN_MAIL_USE_MULTI_PART Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="multipart_x.1648562588.x_boundary" Content-Transfer-Encoding: 8bit --multipart_x.1648562588.x_boundary Content-Type: text/plain; charset=UTF-8 Ceci est un test --multipart_x.1648562588.x_boundary--
I don't think that this is an issue. I use aliases for accounts as well and have no issues with emails getting marked as SPAM. But if you believe that this is an issue, then use the same account for authentication that you use for sending.
As @till said, this is probably not an issue. What matters here is that the domain matches, not the full email address, and you should setup SPF and DMARC for the domain as well as DKIM (which is already done, per the headers you posted). You can look up sender guidelines for gmail and similar services, and the things they say to do/not do will be pretty much what you need to do everywhere to improve delivery.
Ok, those may be working fine then, I just couldn't check because the actual domain name wasn't provided, but could only tell from the headers that it was DKIM signed.
As a side note, using "Subject: Test" will get your email marked as spam on many systems, so that's not suitable for testing purposes when it comes to spam filtering at all.
