Deliverability
Gmail 550 5.7.25: the PTR record Gmail requires, and IPv6
Gmail returns 550 5.7.25 when the sending IP has no PTR record or its forward DNS does not point back to that IP. Check the exact IP in the bounce, IPv6 first.
5 min read
Gmail returns 550 5.7.25 when the sending IP has no PTR record or its forward DNS does not point back to that IP. Check the exact IP in the bounce, IPv6 first.
5 min read