On 07/11/2026 01.10, Jarland Donnell wrote: > Just today we've seen an error that I've never seen before from Microsoft: > >> 550 5.7.1 Message rejected: Message lacks SPF/DKIM/DMARC Auth Records >>(AS9031519) > > In each case, the sender domain has correct SPF and DKIM. From what we're > seeing, > this just seems to trigger when the sender domain doesn't have a DMARC record. > So I guess DMARC is now a requirement to send mail to Microsoft, they're > pulling a Google and applying it at random, or they've targeted us and our > customers for it. This now also seems to have been noted by media:
https://www.theregister.com/applications/2026/11/09/outlookcom-bounces-legit-emails-as-microsofts-authentication-crackdown-goes-sideways/5308428 -- /* * * Otto J. Makela <[email protected]> * * * * * * * * * */ /* Phone: +358 40 765 5772, ICBM: N 60 10' E 24 55' */ /* Mail: Mechelininkatu 26 B 27, FI-00100 Helsinki */ /* * * Computers Rule 01001111 01001011 * * * * * * */ _______________________________________________ mailop mailing list -- [email protected] To unsubscribe send an email to [email protected]
