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p.MsoNormal,p.MsoNoSpacing{margin:0}</style></head><body><div>One quick thought does come to mind. Any chance you're using 2048-bit DKIM and that Yahoo can only work with 1024-bit DKIM? I encountered that in one of my study cases, where the receiving mail system can't verify.2048-bit DKIM.<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">Hartmut<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">On Thu 27 Oct 2022 at 04:45:00 -05:00, Hartmut W Sager <<a href="mailto:hwsager@marityme.net">hwsager@marityme.net</a>> wrote:<br></div><blockquote type="cite" id="qt" style=""><div><span class="qt-font" style=""><span class="font" style="font-family:verdana, sans-serif, sans-serif;">I am now just finishing 3 months of SPF experiences and 1-2 months of DKIM experiences (I'm still weak on DKIM). The stuff mostly works now, but I too have had one identifiable trouble maker, namely Gmail in my case.</span></span><span class="qt-font" style=""><span class="font" style="font-family:verdana, sans-serif, sans-serif;"></span></span><br></div><div style="font-family:verdana, sans-serif;"><span class="qt-font" style=""><span class="font" style="font-family:verdana, sans-serif, sans-serif;"></span></span><br></div><div style="font-family:verdana, sans-serif;"><span class="qt-font" style=""><span class="font" style="font-family:verdana, sans-serif, sans-serif;">I think we need a bit more info from you here. We need the "send from" domain name, the "to" domain name, and the relevant DNS zone file records of the "send from" domain name. (The "to" domain name is only needed in case Internet research has something to say about its DKIM verification efforts.)</span></span><br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;"><span class="qt-font" style=""><span class="font" style="font-family:verdana, sans-serif, sans-serif;">As for (multiple) conflicting DKIM setups on one domain, that should hardly be possible as long as the "selectors" are unique.</span></span><br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;"><span class="qt-font" style=""><span class="font" style="font-family:verdana, sans-serif, sans-serif;">Also note that, while DKIM usually only involves TXT records, one case I have (Fastmail) </span></span>involves CNAME and TXT records.<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">We might ultimately need to see the received header as well.<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">Hartmut<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">On Wed 26 Oct 2022 at 23:14:54 -05:00, Trevor Cordes <<a href="mailto:trevor@tecnopolis.ca">trevor@tecnopolis.ca</a>> wrote:<br></div><blockquote type="cite" id="qt-qt" style=""><div style="font-family:verdana, sans-serif;">We're sending email on behalf of other companies with the From: (company)<br></div><div style="font-family:verdana, sans-serif;">and Sender: (us) set properly. We have DKIM (domainkeys) setup with<br></div><div style="font-family:verdana, sans-serif;">opendkim for outgoing mail. We have the TXT record setup properly.<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">This setup works for all of our customers. Except one, and only (so far<br></div><div style="font-family:verdana, sans-serif;">as we know) with yahoomail. Same setup for every outgoing email, every<br></div><div style="font-family:verdana, sans-serif;">company, same everything. But just these emails just to yahoomail show a<br></div><div style="font-family:verdana, sans-serif;">DK fail. All other emails for the other companies to any mail provider<br></div><div style="font-family:verdana, sans-serif;">show a DK pass.<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">I checked that the customer domain doesn't have a conflicting DK setup,<br></div><div style="font-family:verdana, sans-serif;">and they don't.<br></div><div style="font-family:verdana, sans-serif;"><br></div><div style="font-family:verdana, sans-serif;">I'm really baffled. Makes no sense at all. Anyone have any ideas?<br></div><div style="font-family:verdana, sans-serif;">_______________________________________________<br></div><div style="font-family:verdana, sans-serif;">Roundtable mailing list<br></div><div style="font-family:verdana, sans-serif;"><a href="mailto:Roundtable@muug.ca">Roundtable@muug.ca</a><br></div><div style="font-family:verdana, sans-serif;"><a href="https://muug.ca/mailman/listinfo/roundtable">https://muug.ca/mailman/listinfo/roundtable</a><br></div><div style="font-family:verdana, sans-serif;"><br></div></blockquote><div style="font-family:verdana, sans-serif;"><br></div><div>_______________________________________________<br></div><div>Roundtable mailing list<br></div><div><a href="mailto:Roundtable@muug.ca">Roundtable@muug.ca</a><br></div><div><a href="https://muug.ca/mailman/listinfo/roundtable">https://muug.ca/mailman/listinfo/roundtable</a><br></div><div><br></div></blockquote><div style="font-family:verdana, sans-serif;"><br></div></body></html>