DNS and deliverability
Make sure your messages are delivered and not marked as spam.
DNS records for e-mail
The MX, SPF, DKIM and autodiscover records your domain needs for e-mail hosting.
Set up DKIM
Sign outgoing messages with DKIM to improve deliverability.
Check the delivery log
Find out what happened to a message that did not arrive.
E-mails land in spam or are rejected
SPF, DKIM, DMARC, bounces and the other things that decide whether your mail is delivered.