SPF includes a domain with no SPF record
URGENTWhat it means
include:example.net expects an SPF record at example.net and there isn’t one. Per the RFC that is a permanent error, and strict receivers fail your mail on it.
How to fix it
Remove include:example.net, or correct it to the hostname your vendor actually documents.
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 5.2. 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_INCLUDE_NXDOMAIN
Every fix on this site is yours to implement. If you would rather someone did it, I take this work directly.