Gmail delivery error 550-5.7.26 … time for DKIM
550-5.7.26 This mail has been blocked because the sender is
unauthenticated. 550-5.7.26 Gmail requires all senders to authenticate with
either SPF or DKIM.
Remote server returned '554 5.7.0 < #5.7.26 smtp; 550-5.7.26 Unauthenticated email from domain is not accepted due to 550-5.7.26 domain's DMARC policy. Please contact the administrator of 550-5.7.26 domain if this was a legitimate mail.
If you’re getting email bounce messages like the ones above from Google, it’s time for you to get serious about email authentication for your domain.
Google is ramping up its requirements for senders to use email authentication in 2024 as it combats domain spoofing.
Quick test to see how your domain faires:
Send an email to [email protected] and wait about 30 seconds for a reply message
When the reply arrives (check your junk folder after a few minutes), click on the big red link at the top of the message
On your results page, you want to see the five green checkmarks shown below
If you see red marks, get to work on improving up your email authentication
Repeat this entire process for every system you use that sends emails on your custom domain
Don’t forget stuff like CRM, support desk, mailchimp, etc
Related articles:
Make sure you see all five green checkmarks!
