Skip to main content

How can I use this header to troubleshoot authentication?

Verification: check that expected authentication passes. If **DKIM** shows fail, investigate signing configuration. If **SPF** shows fail, verify sending IP is in **SPF record**. **DMARC** fail indicates alignment issues.

Failure analysis: header details explain failures. "**DKIM signature** mismatch" suggests message modification. "**SPF** fail (ip not permitted)" shows unauthorized sending IP. Specific information guides troubleshooting.

Comparison: check headers on both delivered and filtered messages. Understanding what passes versus fails reveals patterns. Consistent authentication on delivered messages confirms proper configuration.