Folderly Flash Send-readiness test Have Folderly fix this

Check MTA-STS and TLS-RPT readiness

MTA-STS tells other mail servers to use TLS when delivering mail to your domain, and TLS-RPT sends reports when that secure delivery fails. These records are not a replacement for SPF, DKIM or DMARC, but they are part of a mature domain security posture.

Why mailbox providers enforce this

Deliverability starts with identity, but mailbox providers also notice whether a domain is operated like serious mail infrastructure. MTA-STS reduces downgrade and interception risk for inbound mail; TLS-RPT gives you failure visibility. A broken policy, missing HTTPS policy file or report address that bounces can make your security posture look unfinished.

How to fix it

  1. Publish _mta-sts.yourdomain TXT with version, id and an intentional mode.
  2. Host the policy file at https://mta-sts.yourdomain/.well-known/mta-sts.txt with valid HTTPS.
  3. List the MX hosts that should receive mail for the domain and choose testing before enforce if you are not ready.
  4. Publish _smtp._tls.yourdomain TXT with a rua= reporting address for TLS-RPT reports.
  5. Monitor reports before moving to enforce, especially after MX or mail-provider changes.
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

Will MTA-STS improve outbound inbox placement?
Usually not directly. It protects inbound delivery to your domain and signals operational maturity, but SPF, DKIM, DMARC, reputation and engagement still drive outbound placement.
Do I need TLS-RPT with MTA-STS?
Yes if you want visibility. TLS-RPT tells you when senders cannot deliver securely under your policy, which is the feedback loop that makes enforcement safe.

Related

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