Fix DKIM Selector Errors

DKIM failures usually mean the message was not signed correctly, the selector DNS record is wrong, or the provider signed with a different domain than you expected.

Common causes

  • Selector record missing from DNS
  • Wrong public key published
  • Provider-side DKIM disabled
  • Cached old selector after a rotation
  • Signing domain does not align with the visible From domain

Fix sequence

  1. Identify the selector from the message headers.
  2. Confirm the DNS record exists at selector._domainkey.yourdomain.com.
  3. Make sure the provider is signing mail with that selector.
  4. Resend a fresh message after DNS propagation.

What a good result looks like

  • dkim=pass in the receiving system
  • Selector visible in the headers
  • Domain alignment that supports DMARC

If DKIM is configured at the provider but still fails, verify you are testing the same sending stream that the DNS record was created for.