How do I identify blocked recipient mail servers?

Updated Nov 2, 2026

The Blocked & rejecting domains section of the Feedback Loop page lists recipient domains that rejected your email in the last 30 days.

Reading the table

  • Domain and Rejected: the recipient domain and how many emails it rejected.
  • Main reason and Codes: why, grouped as address problems, authentication, reputation or blocklists, content or policy, and rate limits.
  • Senders: which of your senders were affected (hover for the addresses).
  • Status: Blocked, Rejecting or Watch.

What to do

  • Authentication reasons: fix your SPF, DKIM or DMARC records.
  • Reputation, spam or blocklist reasons: slow down, review your audience and content, and see the IP blocklist article.
  • The Sending restrictions section shows senders that are paused for a provider right now.

More details in the FAQ

The FAQ is in the MailRush.io app under Support (sign-in required).

Related articles

Didn't find what you need?

Sign in to MailRush.io and open a support ticket, and our support team will get back to you.

Contact support