My Mautic version is: 6.0.0
My PHP version is: 8.3.19
My Database type and version is: 10.11.11-MariaDB-cll-lve
In Mautic’s settings, I have info@domain.com configured as the sender and SMTP set up in Mailrelay.
However, when sending an email from Mautic, I get this error:
Expected response code “250/251/252” but got code “550”, with message “550 [E3] Message rejected because sender’s email is not confirmed.”
When I check the Mailrelay log, this is the result:
02/04/2025 01:26:38 info+bounce_67ec762e15585784344497@domain.com test@gmail.com [E3] Message rejected because sender's email is not confirmed.
It looks like Mautic is trying to send the email using this address (which doesn’t exist or isn’t configured):
info+bounce_67ec762e15585784344497@domain.com
info is the main email, and bounce is the one I have set up for bounces. Somehow, Mautic is merging them and adding an underscore and a random ID before the @.
Why is this happening, and how can I fix it?
(The addresses I mention in the post are fictitious, but we can assume that I have real addresses configured.)