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<p dir="auto">On 27 Jan 2019, at 18:06, Robert Brenstein wrote:</p>
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<div style="white-space:normal"><blockquote style="border-left:2px solid #777; color:#777; margin:0 0 5px; padding-left:5px"><p dir="auto">Such notifications are most often prompted by the sending host, that is the list host, suddenly deemed to be a spammer.</p>
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<p dir="auto">This could be the problem, but I don't think this is the case. I use a third party service to monitor the reputation of my server and it has had no problems.</p>
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<div style="white-space:normal"><blockquote style="border-left:2px solid #777; color:#777; margin:0 0 5px; padding-left:5px"><p dir="auto">Usually, it is a side-effect of some other user of that same service causing the IP (IP range) to be blacklisted. In this case, it might have been only Google thinking so, rightfully or not. Google, AOL, a few other services also count the number of recipients in each instance of mail and if they adjusted that limits, blacklisting would be the result.</p>
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<p dir="auto">The issue seems to at least partly be caused by at least 1 user using the DMARC <code style="background-color:#F7F7F7; border-radius:3px; margin:0; padding:0 0.4em" bgcolor="#F7F7F7">reject</code> option. All users on email servers which respect this option (Gmail, iCloud, ...) are going to bounce emails from such a user. These bounces are going to add up on my server (there's a MailMan score system for this) and when it reaches a certain limit they are “unsubscribed” (they are actually only disabled at first).</p>
<p dir="auto">I'm deliberately trying to be vague here. When googling the subject you might notice that any statement about SPF/DKIM/DMARC is quickly followed by discussions about how things really work -- in theory or practice. I'm now at the point where I would automatically become suspicious if anyone (any webpage) seems to claim to fully understand the consequences of any kind of setup/setting related to this :-)</p>
<p dir="auto">As a short term solution I've now disabled bounce processing on my mailing list software. This is mainly a problem for me and not my users. This won't change the fact that some emails (at least from 1 user) is not going to be received by a lot of other users.</p>
<p dir="auto">If you want to see if you missed a reply to one of your emails then look here: <a href="https://www.mail-archive.com/mailmate@lists.freron.com/" style="color:#3983C4">https://www.mail-archive.com/mailmate@lists.freron.com/</a></p>
<p dir="auto">Data point: 89 mailing list members out of 474 have been unsubscribed (some have probably resubscribed now).</p>
<p dir="auto">-- <br>
Benny</p>
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