I’m trying to figure out how to get discourse to clean up email lists, specifically bounced emails. The site is using a private smtp server to send emails but the response is set to came back to a gmail address for POP access by discourse. So I see bounced emails in the Received emails dashboard. [image] However under the Bounced emails dashboard, there’s nothing [image] When I look at the Discourse error logs, I do see that it’s detecting a bounced email Email can not be processed: Email::Receiver::BouncedEmailError Delivered-To: xxx.yyy@gmail.com Received: by 2002:xxx:7022:911:xx:73:xxx:f96 with SMTP id xxx7csp1115046dlb; Thu, 25 Jan 2024 12:03:33 -0800 (PST) X-Google-Smtp-Source: AGHT+IEagzW8QOUgAyfOxU9wYaox/wuiL/wNqWhvftUB4uO/85r9H/55+FnfT6NrSTkLI5kfj+Vy X-Received: by 2002:xxx:620a:4xxx:b0:xxxx:9265 with SMTP id br34-xxx8ba09265mr280168qkb.77.17062130xxx; Thu, 25 Jan 2024 12:03:33 -0800 (PST) Return-Path: <> Received: from xxx.com (xxx.com. [207.xxx.xxx.xxx]) by mx.google.com with ESMTPS id bi4-xxx0b00783c84e9ef8si590747qkb.206.xxx.01.xx.12.03xxx for xxx.yyy@gmail.com (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Jan 2024 12:03:33 -0800 (PST) Received-SPF: none (google.com: xxx.com does not designate permitted sender hosts) client-ip=207.xxx.xxx.xxx; Authentication-Results: mx.google.com; dkim=pass header.i=@xxx.co.nz header.s=alpha header.b=biFVvXep; arc=fail (signature failed); spf=none (google.com: xxx.com does not designate permitted sender hosts) smtp.helo=xxx.com; dmarc=pass (p=NONE sp=REJECT dis=NONE) header.from=xxx.co.nz Received: from xxx.co.nz (xxx.co.nz [210.xxx.xxx.5x]) by xxx.com (Postfix) with ESMTP id 4DD66xxx8E3 for xxx@zzz.com; Thu, 25 Jan 2024 20:03:28 +0000 (UTC) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zzz.com; s=dkim; t=1706213008; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: dkim-signature; So the question is Why isn’t discourse marking bounced emails as bounced and how do I correct this?

Discourse uses the reply_key to associate bounces with sent emails. When Discourse sends mail, it uses the reply_by_email_address value as the SMTP envelope sender. You need to ensure your reply_by_email_address includes a {reply_key} so your instance can associate the bounces with the correct sent mail. For instance, here on meta it’s set to incoming+%{reply_key}@meta.discoursemail.com and anything set to that address gets delivered to this instance.

Thanks for the response. Unfortunately I’ve had to turn off the reply_key from the response to email because on our email relay server doesn’t recognize the + addressing. Is there any other option?

Okay to clarify, the destination SMTP domain server which receives the bounced email doesn’t recognize the + addressing, so it only forwards emails based on the To field to the gmail address which is picked up by discourse via POP. That if the To field includes the reply_key then it won’t forward that email to the gmail account used by discourse. So I can’t put the reply_key in the email address, can it put somewhere else? In the subject field or body or somewhere where discourse may be able to parse it?

[image] RBoy: the destination SMTP domain server which receives the bounced email doesn’t recognize the + addressing, so it only forwards emails based on the To field to the gmail address which is picked up by discourse via POP It would help a lot if you wrote what you were actually using for settings, even anonymised slightly. You might also want to look into setting alternative_reply_by_email_addresses. [image] RBoy: can it put somewhere else? I don’t believe so. If possible, for your setup I’d recommend something like: set reply_by_email_address to inbound+%{reply_key}@forum.hostname configure a mail server to receive email for forum.hostname and deliver it all to the.gmail.account@gmail.com Here the intermediate mail server doesn’t need to understand plus-addressing, it just needs to forward on everything for the domain.

Absolutely Email parsing setup: [image] Email sending setup: [image] The email sent by Discourse goes from discourse@xxx.com via a dedicated domain SMTP server setup for discourse (using the discourse domain address). Any replies or when email bounces back, the domain SMTP server forwards the email to discourse.xxxx@gmail.com. This domain SMTP server cannot recognize the + addressing, so if I include the reply_key in the reply to email address, it’ll get dropped by the domain SMTP server. I can only set rules to forward discrete/unique incoming email addresses. The discourse forum then uses POP via GMail to access those forwarded replies/bounced emails and parses them. Does this help?

I understand what you’re saying. Unfortunately due to a limitation of the SMTP server rules I cannot setup forwarding for sub domains, I can only configure it to forward unique To emails id’s. However I have a clarification here - more like a discrepancy in how discourse appears to be working: When a user replies to an email post, it comes in correctly - replies seem to work perfectly even without any {reply_key} explicitly configured anywhere (see the screenshots above) However, when an email gets bounced, Discourse categorizes it under Received rather than Bounced The error logs are showing that something in discourse recognizes that it’s a bounced email (see my first post error log). So if something in discourse is recognizing that it’s a bounced email, why doesn’t is show up under Bounced instead of Received? So why is that when a user replies to a post it is processed correctly by discourse but not a bounced email (and there also appears to be a disconnect between the error logs and the dashboard for bounced emails). Am I missing something in the configuration?

I’ve also tried setting the reply by email address settings in discourse to discourse.xxx+%{reply_to}@gmail.com but then when the email gets delivered, gmail seems to think that the domain yyy.com (discourse SMTP domain) is trying to spoof the gmail domain and it ends up marking it as spam. It appears that setting a reply to domain different from the senders domain is triggering a DMARC and SPF failure. ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning discussion.xxx+verp-b9c40db917ca04993dd3433cc9748518@gmail.com does not designate y.y.y.y as permitted sender) smtp.mailfrom=discussion.xxx+verp-b9c40db917ca04993dd3433cc9748518@gmail.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=yyy.com Return-Path:

[image] RBoy: So why is that when a user replies to a post it is processed correctly by discourse but not a bounced email (and there also appears to be a disconnect between the error logs and the dashboard for bounced emails). You’ve turned off find related posts with key (I hope you read the warning) thus Discourse is using the in-reply-to mail header to determine to which topic/post the reply should be referencing. It can’t do that for bounces - Discourse needs to know the specific message which bounced and that information is only guaranteed to be in one spot - the To: address (which comes from the envelope-from address of the original message). For this to work, when Discourse sends a message, it needs to receive the reply to the address from which it came. Discourse looks in the To: header for this (not the envelope-to). [image] RBoy: is trying to spoof the gmail domain is spoofing the gmail domain [image] RBoy: It appears that setting a reply to domain different from the senders domain is triggering a DMARC and SPF failure. If you want to send mail from a gmail address, you need to send it via their servers. But they don’t like that. [image] RBoy: ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning discussion.xxx+verp-b9c40db917ca04993dd3433cc9748518@gmail.com does not designate y.y.y.y as permitted sender) smtp.mailfrom=discussion.xxx+verp-b9c40db917ca04993dd3433cc9748518@gmail.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=yyy.com Return-Path: Doesn’t look like you’ve configured DKIM for yyy.com; you should do that. If you get that right, DMARC should pass.

[image] Michael Brown: Doesn’t look like you’ve configured DKIM for yyy.com Yes it’s configured and the email “sent” by discourse via the yyy.com SMTP server passes SPF, DKIM and DMARC without issues (atleast from the “Send test email” page in the admin console). This issue is happening if I set a gmail address as the reply_by_email_address to a gmail.com address instead of the yyy.com address. Is there something I can do for this setup so that DMARC doesn’t fail when set to reply_by_email_address to a gmail address while keeping the outgoing server as yyy.com ? [image] Michael Brown: For this to work, when Discourse sends a message, it needs to receive the reply to the address from which it came. Discourse looks in the To: header for this (not the envelope-to). Can it not parse the rest of the content/attachments in the bounced email to extract that information if it can’t what it need in the “obvious” place (or atleast provide an option in settings to do that with the necessary warnings about impersonation)

Bounced emails not being detected

Product Support

supermathie (Michael Brown) January 30, 2024, 7:11pm 4

Your email relay server shouldn’t matter, only the end server where the mailbox lies. Email localparts are opaque to any intermediate servers.

Is it not gmail as per:

I’m not sure if we have another mechanism to reliably detect bounces.

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Bounced emails not being detected

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