Folderly Flash Send-readiness test Have Folderly fix this

Read your email authentication breakdown

A single 'authentication: pass' label hides the details that actually explain deliverability failures. A useful authentication breakdown separates the message verdicts from the DNS controls behind them: SPF authorization, SPF alignment, DKIM DNS, DKIM alignment, DMARC policy, reverse DNS/HELO, MTA-STS/TLS-RPT and BIMI readiness.

Why mailbox providers enforce this

Mailbox providers evaluate identity as a chain. If one link is vague, a sender can waste days fixing the wrong thing: SPF passes but does not align, DKIM passes with an old selector, DMARC exists but does not enforce, or reverse DNS makes dedicated infrastructure look disposable. Breaking auth into sub-checks turns a generic failure into a fixable DNS or header task.

How to fix it

  1. Start with message-level verdicts: SPF pass/fail, DKIM pass/fail and DMARC pass/fail from the received authentication results.
  2. Split SPF into DNS health and alignment, because a syntactically correct SPF record can still fail DMARC alignment.
  3. Split DKIM into selector DNS, key quality and alignment, because a DKIM fail can come from DNS, signing or message modification.
  4. Split DMARC into record validity, reporting, policy strength, subdomain policy and the actual SPF/DKIM alignment path.
  5. Add infrastructure checks for dedicated senders: reverse DNS, forward-confirmed hostnames and HELO/EHLO naming.
  6. Track security/readiness checks separately: MTA-STS, TLS-RPT and BIMI should inform the report without pretending they replace inbox-placement testing.
Don't guess — measure it. Send one email to Folderly Flash and see exactly which checks pass or fail for your message, in 30 seconds. No signup.
Run a free test →

FAQ

Why not show one authentication score?
Because one number hides the repair path. A sender with SPF alignment broken needs a different fix than a sender with a missing DKIM selector or DMARC p=none.
Are MTA-STS and BIMI part of DMARC?
No. They are separate domain-security and brand-readiness controls. They belong in a deliverability audit because they show operational maturity, but SPF, DKIM and DMARC remain the core sender-authentication checks.

Related

Want a deliverability engineer to fix this for you? Hand it to Folderly →