On Thursday, May 5, 2016, Christopher Browne &lt;<a href="mailto:cbbrowne@gmail.com">cbbrowne@gmail.com</a>&gt; wrote:<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><div>We&#39;ve had some issues with handling email coming from Yahoo! that seems<br></div><div>to relate to some anti-spam mechanisms.<br></div></div></div></div></blockquote><div><br></div>Hopefully someone will find this interesting. <div><br></div><div>I solved **The Great Unsubscribe Event of 2016** by adding ALLOW_FROM_IS_LIST = Yes the penguin&#39;s mm_cfg.py file. It&#39;s a new option available in Mailman version 2.1.16 that doesn&#39;t require that annoying Reply-To workaround.</div><div><br></div><div>You can read more over on Mailman&#39;s documentation: &lt;<a href="https://wiki.list.org/DOC/What%20can%20I%20do%20about%20members%20being%20unsubscribed%20by%20bounces%20of%20Yahoo%20user&#39;s%20posts%20for%20DMARC%20policy%20reasons%3F">https://wiki.list.org/DOC/What%20can%20I%20do%20about%20members%20being%20unsubscribed%20by%20bounces%20of%20Yahoo%20user&#39;s%20posts%20for%20DMARC%20policy%20reasons%3F</a>&gt; (sorry that links probably not going to work as it&#39;s impossible to share with all those spaces).</div><div><br></div><div>I also subscribe to the mailing list with my Yahoo email address so I can prevent this stuff faster. </div><br><br>-- <br>Myles Braithwaite | <a href="http://mylesb.ca/e" target="_blank">http://mylesb.ca/e</a><br>