Docs Error Library Connection Errors Error 550-5.7.1: Unauthorized Email Rejection

Error 550-5.7.1: Unauthorized Email Rejection

What Is Causing This Error?

‘Error 550-5.7.1’ arises when the sender is flagged as unauthorized by the recipient’s email server, often for security reasons to prevent spam. This error is particularly common with Gmail, which may block emails from an IP address it identifies as sending an unusual rate of unsolicited mail.

The causes include being on a blacklist, failing email authentication checks with SPF, DKIM, or DMARC, or exhibiting behavior that email providers perceive as spam-like.

Resolving the Error – Solution

To resolve Error 550-5.7.1 and particularly address Gmail’s spam filters:

  1. Review Email Sending Practices: Ensure you’re not sending unsolicited emails which could be marked as spam.
  2. Implement Email Authentication: Set up SPF, DKIM, and DMARC records to authenticate your emails. For more details, check out Google’s guide on configuring DKIM and SPF authentication.
  3. Configure SMTP Plugins Properly: If using an SMTP plugin like Easy WP SMTP, make sure it aligns with email authentication standards.
  4. Check for IP Blacklisting: Determine if your IP is blacklisted by Gmail and follow procedures for delisting.
  5. Reduce Email Volume: Temporarily lower the volume of emails sent to avoid triggering spam filters.

That’s it! Now you know the common causes of the ‘550-5.7.1′ error and how to resolve it.

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