HighAuthentication · usually high

SPF record contains a syntax error

Part of the record is not valid SPF, so receivers may reject the whole record.

Check your own domain

What causes this

SPF has a strict grammar: a version tag, then a sequence of mechanisms and modifiers separated by single spaces. A malformed term — a typo in a mechanism name, a stray character, a missing colon — makes the record invalid. Some receivers stop at the bad term, others return permerror for the entire record, so the observable behaviour is inconsistent and hard to debug.

What it breaks

SPF results become unreliable and differ between receivers. Mechanisms after the error may be ignored entirely.

How to fix it

Correct the invalid term so the record parses cleanly.

  1. Review the flagged term against the SPF grammar.
  2. Check for the usual causes: a space inside an include value, a missing colon after include, a smart quote pasted from a document, or two mechanisms run together.
  3. Republish the corrected record and re-check.

Specification: RFC 7208 — Sender Policy Framework

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