Emails going to spam? Work through 12 common causes, from missing SPF, DKIM and DMARC to blocklists, poor lists and risky content, with a fix for each.
What an SPF record does, how its mechanisms and qualifiers work, and how to build, publish and test a correct SPF record for your domain step by step.
Why SPF too many DNS lookups errors happen, how to count lookups in your record, and five safe ways to bring your SPF record back under the limit of 10.
SMTP ports 25, 465, 587 and 2525 explained: what each is for, how STARTTLS and implicit TLS differ, and which port your app or device should use.
What an MX record is, how priorities and backup servers work, the rules MX targets must follow, and how to check and change MX records without losing mail.
What MTA-STS and TLS-RPT do, why opportunistic STARTTLS is not enough, and how to publish the DNS records and policy file to enforce encrypted delivery.
Why new sending domains and IP addresses land in spam, and a practical week-by-week plan to warm them up and build a good sending reputation.
A step-by-step email migration plan for businesses: prepare the new provider, copy mailboxes, switch MX records, update SPF and DKIM, and tidy up.
A practical DKIM setup guide: how signing works, enabling it in Google Workspace and Microsoft 365, signing your own server with OpenDKIM, and testing.
A field-by-field guide to DMARC reports: what the XML contains, how to tell legitimate senders from spoofers, and what to fix before you enforce.
The Gmail sender requirements and Yahoo rules explained: authentication, DMARC, one-click unsubscribe and spam rates, with a practical checklist to comply.
How to read an email bounce message, the difference between soft and hard bounces, and what the most common SMTP codes such as 550 and 554 mean and how to fix them.
