SPF mistakes, troubleshooting, and validation

This post is part of the Email Security Foundations series. The mistakes that break SPF quietly SPF usually does not fail in loud or obvious ways. Mail does not bounce with a helpful error message. It just gets filtered, delayed, or rejected somewhere else. You only find out when someone eventually asks, “Did you get … Read more

SPF deep dive – how it works and how to configure it

This post is part of the Email Security Foundations series. What SPF actually does SPF, Sender Policy Framework, is simply a way to publish a list in DNS of which servers are allowed to send email for your domain. When a receiving mail server gets a message claiming to be from yourdomain.com, it looks up … Read more