All Collections
Why do I see a "null DNS lookup" when I use a certain DNS scanner?
Why do I see a "null DNS lookup" when I use a certain DNS scanner?
Updated over a week ago

Some Valimail customers have noticed on some security sites that various DNS, DMARC, and SPF records may be reported as "problematic" for users.

Various companies have sections of their sites set up to check DNS records for DMARC status or other tasks to report risk levels. In fact, we have a domain checker on our own site at

However, some email security sites only take a rudimentary approach to their scans. One of these is MX Toolbox. MX Toolbox's SPF checker or DNS scanner cannot parse SPF macros if domains are leveraging that type of record. Their UI will usually report a problem of a "A null DNS lookup was found for include.....".

Macros are part of the SPF spec and have been for many years. Part of the problem for these free checkups is that not all of them can actually create the full SPF query that is needed. You can be assured that if you have a SPF record leveraging macros as our standard Valimail record does then your domain is compliant.

We have many other articles about SPF macros in our KB. Please check those for additional information or feel free to reach out to our Support Team should you have further questions.

Did this answer your question?