HighAuthentication · usually high

No SPF record found

This domain publishes no SPF record, so receivers have no list of authorised senders.

Check your own domain

What causes this

SPF is a TXT record at your domain listing which mail servers are allowed to send email using your domain in the envelope sender. Without it, a receiving mail server has nothing to compare an incoming message against, so the SPF check returns 'none'. Google, Yahoo and Microsoft all expect bulk senders to publish SPF, and a missing record is one of the first things their filters notice.

What it breaks

Messages from your domain cannot pass SPF. Because DMARC needs either SPF or DKIM to pass with alignment, a missing SPF record also removes one of the two ways your mail can satisfy DMARC.

How to fix it

Publish a TXT record at your domain listing every service that sends mail as you.

List every system that sends email using your domain: your mailbox provider, and any marketing, billing, ticketing or application services.
Find the SPF include value each of those providers documents (for example include:_spf.google.com).
Combine them into a single TXT record at your root domain — there must be exactly one SPF record.
End the record with ~all so unlisted senders are marked as a soft failure while you confirm the list is complete.
After a week with no legitimate mail being marked as a failure, consider tightening ~all to -all.

Example record

TXT · @

v=spf1 include:_spf.google.com ~all

Replace the include with the values your own sending providers publish.

Specification: RFC 7208 — Sender Policy Framework