How to Fix SPF Fail

A practical checklist for fixing SPF failures without breaking legitimate email senders.

Find the real sending service

SPF fails when the server that delivered the message is not authorized by the domain's SPF record.

Check your mail provider, newsletter tool, CRM, support desk, and transactional email provider before editing DNS.

Publish one TXT record that starts with v=spf1. Merge includes instead of creating multiple SPF records.

After changes, test again and watch for DNS lookup limits if the record has many include mechanisms.

Recommended next steps

Turn this guide into a concrete DNS report for your own domain.

Generate SPF and DMARC records before publishing DNS changes.

Find the SPF TXT record that controls which senders can mail for a domain.

Paste raw email headers to inspect routing hops, authentication results, and message metadata.

Forwarding often breaks SPF because the forwarding server is not listed in the original sender's SPF record.

Use ~all while testing. Move to -all only after you know every legitimate sender is included.