SPF exceeds the 10-lookup limit
CODE REDWhat it means
Evaluating your record costs N DNS lookups; the limit is 10. Receivers return a permanent error and stop trusting SPF, so your mail fails authentication even from your own servers.
How to fix it
Cut lookups back under 10: drop unused vendor includes, replace stable includes with their ip4:/ip6: ranges, or run the free SPF Flattener and publish the flattened record.
Check your own domain
This page describes the condition. To find out whether your domain has it, run the SPF test or the full checkup, which examines every record at once.
Understand it properly
This page covers one condition. For the whole picture, What is SPF, and the ten-lookup limit, or start at the Health Library.
Where this comes from
We judge this against RFC 7208 section 4.6.4. Every finding on this site cites the specification behind it so you can check the work rather than take our word for it.
Other SPF conditions
SPF_LOOKUP_LIMIT_EXCEEDED
Every fix on this site is yours to implement. If you would rather someone did it, I take this work directly.