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Barracuda Blacklist Removal: How to Check and Delist Your IP

Published 2026-11-03 ／ Updated 2026-11-03 ／ By Yuki Nakazawa

Barracuda blacklist removal comes down to three steps: confirm from the bounce and Barracuda's own lookup page that you are really on the Barracuda Reputation Block List (BRBL), fix whatever caused the poor rating, then send one removal request through the official form. The BRBL is the IP reputation database run by Barracuda Central. Barracuda's email security products use it, and other mail servers can query it as a standard DNS blocklist.

Barracuda's removal page says that requests with a valid explanation are typically investigated and processed within 12 hours. It also says that requests without valid information, and repeated requests, are ignored. The decision to delist rests with Barracuda.

This guide is based on the official Barracuda pages we could access in November 2026. The BRBL usage page could not be loaded at the time, so the DNS query details below come from an archived copy of that official page from March 2023. Check Barracuda's site before you file anything. If you are still working out why mail is bouncing in general, start with our guide to email blocked by blacklists.

What the Barracuda Reputation Block List is

According to Barracuda's product documentation, Barracuda Reputation is a database maintained by Barracuda Central. It holds IP addresses of known good senders as well as known spammers and other senders with a poor reputation. The data is collected from spam traps (addresses that exist only to catch unsolicited mail) and other systems across the internet, and the sending history of each sending mail server's IP address is analyzed. Barracuda Central engineering updates it continuously.

Barracuda Central's lookup page describes the Barracuda Reputation System as a real-time database of IP addresses that have a poor reputation for sending valid email. The removal request page adds that the BRBL is generated by automated systems, while the lookup page says Barracuda Central also manually verifies the IP addresses marked as "poor". In practice, your rating mostly reflects how mail from your IP has been observed to behave, rather than a one-off judgment about your company.

The archived BRBL usage page explains that the list is also published as a standard DNSBL in the zone b.barracudacentral.org, and that it can be used by many common mail servers and anti-spam products, not only Barracuda appliances. So a BRBL listing can cause rejections at organizations that run their own mail servers with the BRBL enabled, not only at Barracuda customers. For background on how DNS blocklists work, see what a DNSBL or RBL is.

Reading the bounce: BRBL or something else?

Before you do anything else, read the full bounce message. Barracuda's SMTP error code reference for the Email Security Gateway lists the rejection texts below. Telling them apart saves you from filing a removal request for a list you are not on.

In Barracuda's reference, the BRBL rejection text is followed by a link to Barracuda's reputation page. Wording can vary with the product and the recipient's configuration, so treat the table as a guide rather than an exact match.

The rule of thumb: if the bounce says "blocked using Barracuda Reputation", you are dealing with the BRBL. If it does not, the cause is more likely another blocklist or the recipient's own policy. You can check many other lists at once with our blacklist checker, and our guide to DNSBL response codes explains how to read the answers.

How to check whether you are on the BRBL

1. Identify the sending IP. The BRBL rejection text includes the IP address or hostname that was blocked. If you cannot find it, look at the Received headers of a message you sent, or ask whoever runs your mail server. Your website and your mail may not leave from the same address.
2. Use the official lookup. Enter the IP address or domain in Barracuda Central's Reputation Lookup (barracudacentral.org/lookups). The lookup page also links to Barracuda's explanation of why an IP may be listed.
3. Write down the result and the time. You will want them for the removal request and for any conversation with your hosting provider or the recipient's administrator.

You can also query the DNS zone directly. As with any DNSBL, you reverse the octets of the IP and append the zone. The archived usage page uses the standard test address 127.0.0.2 as its example; if the blocklist accepts queries from your resolver, it should return 127.0.0.2:

host 2.0.0.127.b.barracudacentral.org
nslookup 2.0.0.127.b.barracudacentral.org

There is a catch. That same page describes direct DNS access as something you request first: the IP addresses of the name servers making the queries are registered with Barracuda and approved before use. From an unregistered resolver, you may not get a meaningful answer. For a yes or no on your own listing, the official lookup page is the more reliable source.

How to submit a Barracuda removal request

Removal requests go through Barracuda Central's Removal Request page (barracudacentral.org/rbl/removal-request).

1. Fix the cause first. Work through the causes in the next section and resolve them before you file. Because the list is generated by automated systems, an IP that keeps behaving the same way can earn a poor rating again.
2. Fill in the form. The page asks for your email server's IP address, your email address, a phone number and an optional reason for removal. The form also has fields for a Barracuda customer name and a Barracuda customer email address. Required fields are marked in bold on the page.
3. Write a real explanation. The page says requests are typically investigated and processed within 12 hours if they come with a valid explanation. State briefly what went wrong, what you changed and when. "Please remove us" on its own is not an explanation.
4. Submit once. Barracuda states plainly that requests without valid information will be ignored, and that multiple requests will also be ignored.

A request is not a promise of delisting; Barracuda makes the call. The official pages we reviewed do not mention any fee, and the form is on Barracuda's own site. If the IP is not yours to manage, for example a shared address at a web host or an email service, contact that provider rather than filing on their behalf. Our guide to shared hosting IPs on blacklists covers that situation.

Why IPs get listed, and what to check before you file

Barracuda Central lists these reasons a legitimate IP may be marked as poor:

• Your mail server is infected with a virus and has been sending spam.
• Your mail server is configured incorrectly.
• Your own PC is infected with a virus or botnet software.
• Someone else in your organization has an infected PC.
• You are on a dynamic IP address that a known spammer used before you.
• Your marketing team is sending bulk email that does not comply with the US CAN-SPAM Act.
• An unsecured wireless network is letting strangers send spam through your connection.
• In rare cases, the recipient's Barracuda appliance is misconfigured.

Turn that list into a checklist before you file:

• Compromised accounts. Look for sending spikes you cannot explain in your mail logs, and reset any password that may have leaked.
• Devices and network. Scan the machines that share the connection, and make sure your wireless network is encrypted with a strong password.
• Bulk mail practices. Stop sending to old or purchased lists, mail only people who asked to hear from you, and give every message a working unsubscribe option.
• Server configuration. Make sure the sending IP has a PTR record. As the table above shows, a missing PTR can get you rejected on its own.
• One recipient or many? If only one organization rejects you while everyone else accepts your mail, their configuration may be part of the problem.

If you have not set up sender authentication yet, review SPF, DKIM and DMARC as well. It will not prevent a listing on its own, but it helps you spot spoofing and builds trust with receivers.

Preventing relisting, and what to do if mail still bounces

Since the BRBL is driven by observed sending behavior, assume that the same problem will bring the same result. Habits that keep you off it:

• Watch your sending volume and bounce rate, and stop a campaign or account the moment numbers jump.
• Use unique passwords, and turn on two-factor authentication wherever your mail platform supports it.
• Keep servers, CMS installations and desktops patched.
• Prune your mailing lists and send only to people who opted in.
• Check your IPs against blocklists regularly, either with our blacklist checker or with an automated monitor.

If you have been delisted but one particular recipient still rejects you, their setup may be the issue. Barracuda's documentation explains that administrators can exempt trusted sender IP addresses from BRBL checks, and can override block lists with IP or sender filters. In Email Gateway Defense, messages blocked by the BRBL are not sent to the end user's message log, so the person you are writing to may not see your messages at all (an administrator can still see the "Barracuda Reputation" reason in the admin Message Log). Send their administrator the full bounce text, your sending IP and the time of the failure so they can check.

If tracing the cause or dealing with the recipient's IT team is more than you can take on, you can ask us for help.

FAQ

Official pages used

The facts in this article were checked against the official pages below at the time of publication. Policies and behavior change without notice, so check the official pages before relying on anything important.

• Barracuda Central: Reputation System Removal Request
• Barracuda Central: IP / Domain Lookups (Barracuda Reputation)
• Barracuda Central: Why is my IP listed on the Barracuda Reputation System?
• Barracuda Central: BRBL How to Use (archived copy, March 2023)
• Barracuda Email Security Gateway: SMTP Error Codes
• Email Gateway Defense: Barracuda Reputation and Email Categorization
• Email Gateway Defense: Message Actions
• Barracuda Email Security Gateway: IP Analysis Inbound

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