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Barracuda BRBL error (Barracuda): The sending IP is on the Barracuda block list

Barracuda Reputation Block List lists this IP, and Barracuda-protected recipients refuse mail from it.

permanentHard bounce · Reputation or blocklist · Barracuda

How to fix Barracuda BRBL

  1. Check the IP on the Blacklist Checker and use Barracuda's free removal request.
  2. Fix the cause - high volume to bad addresses, a compromised account or an open relay - or it will be relisted.

Check the IP and domain on the Blacklist Checker →

Why this happens

Receivers score every sending IP and domain. A history of complaints, spam-trap hits, high bounce rates or a listing on a blocklist pushes that score down until mail is deferred or refused outright.

How to keep it from coming back

Warm up new domains and IPs gradually, send only to verified and relevant recipients, keep complaints near zero, and check your IPs and domains on blocklists regularly. Spread volume across mailboxes and domains instead of pushing one harder.

Should I retry a Barracuda BRBL error?

Not as it stands. A permanent error means the same message will be refused again until the cause is fixed on your side. Fix the cause first, then send a fresh message; if it keeps failing after that, check the full text of the bounce for the exact reason.

Got the full bounce message?

The text after the code names the exact reason, and the same code can mean different things at different receivers. Paste the whole message into the decoder - it runs in your browser and nothing is sent.

Open the bounce decoder

Related error codes

Seeing this again and again? That's usually a reputation or authentication problem we can trace and fix at the source.

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