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ZeroHook | SecurityTools

What should I do

Fix 550 5.7.26

Authenticate the server that sent the message with SPF or DKIM. On direct mail, Google also requires that domain to align with the From header.

  • Publish one SPF record that names every server that sends for the domain. Two records that both start with v=spf1 are a permerror.
  • Turn on DKIM at the provider and publish the key it gives you.
  • Publish a DMARC record at _dmarc. Bulk senders, in Google's guidelines, need SPF, DKIM, and DMARC. Every sender needs SPF or DKIM.