I'm running Mailman version 2.1.29. I have a Mailman email list that has around 500 subscribers, who are all members of an organization who have opted-in to the list.
One of the email addresses on the list used a custom personalized domain, which started bouncing. I didn't notice the bounces at the time. Eventually, Google started sending the list moderators messages saying "Our system has detected an excessively high number of invalid recipients originating from your account," and Gmail started rejecting list messages that were being sent to the list subscribers who use a Gmail address. I removed the bouncing email address from the list, and soon after that Gmail started accepting messages from the email list again. This seems like a very precarious situation to be in... I have a list of 500 email addresses, and Google starts rejecting all incoming email from my list just because 1 of 500 email addresses was bouncing. I sought help from someone at my hosting provider who seems to be knowledgeable about Mailman configuration. He said that the problem was that Mailman was batching up the emails and sending a single email to the entire batch, putting each individual email address in the "RCPT TO" field. So when a bounce happened, Gmail was able to associate the bad address from my domain with the bounce that was happening on the bouncing personalized domain. The advice for fixing the problem was to set the "personalize" setting to "Full Personalization", which would prevent Google from making that association. I think this worked (but don't know for sure, since I don't know that we've had any bounces since then). The problem with "Full Personalization" is that the email headers are being rewritten, which is confusing to users. Now, if someone sends an email to the list, the message that is delivered to each recipient has the recipient's email address in the "To" header and the list email address in the "Cc" header. It works, but it's confusing (and some people's email filters now have to be changed). Questions... 1) Given my description of the initial problem, is "Full Personalization" the best way to fix the issue? 2) Is there a way to fix the issue that doesn't involve rewriting the headers so that the email list address is in the "Cc" field? 3) Would upgrading to Mailman 3 help fix this issue in a better way? Thanks Mike ------------------------------------------------------ Mailman-Users mailing list -- email@example.com To unsubscribe send an email to mailman-users-le...@python.org https://mail.python.org/mailman3/lists/mailman-users.python.org/ Mailman FAQ: http://wiki.list.org/x/AgA3 Security Policy: http://wiki.list.org/x/QIA9 Searchable Archives: https://firstname.lastname@example.org/ https://email@example.com/