This article covers the causes and solutions for activation emails and password reset emails being rejected with the following error:
550 5.7.26 Unauthenticated email from https://login.example.com is not accepted due to domain's DMARC policy. Please contact the administrator of https://login.example.com domain if this was a legitimate mail. Please visit https://support.google.com/mail/answer/2451690 to learn about the DMARC initiative.
- DMARC
- Email Reject
- Custom Domain
DMARC Policy is set to p = reject.
- Check the email header for the rejected email. It will have a DNS value (that is,
"v=DMARC1; p=reject). - Using https://mxtoolbox.com/, perform a DMARC lookup for the Tenant URL in question.
- If the value p=reject is seen, then update it to p=none.
