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As of March 1, 2022, the legacy Barracuda Essentials Security, Compliance, and Complete editions are no longer available for purchase. Only existing customers can renew or add users to these plans. The documentation related to these plans will no longer be available after October 30, 2022. For more information on the latest Email Protection plans, see Barracuda Email Protection.

To update your bookmarks, see the following for the latest documentation:

Note that MSP customers should continue to follow Barracuda Essentials for MSPs.

Outbound Mail Scanning

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Before using the Barracuda Email Security Service outbound filter, go to and verify that your outbound IP address is not on the Barracuda Reputation list. If present on the list, contact Barracuda Networks Technical Support and request removal before using the outbound service.

Table 1. Outbound Mail Settings.

Outbound Mail Scanning
All messages, inbound and outbound, routed through Email Gateway Defense are subject to a 300MB size limit. This includes all headers, body, and attached content. This size can be lowered on a per domain basis by contacting Barracuda Networks Technical Support.

Outbound mail scanning includes:

  • Spam Scanning with Block or Quarantine actions
  • Virus Scanning  
  • IP Address Filtering
  • Sender Domain, Username or Email Address Filtering
  • Recipient Email Address Filtering
  • Content Filtering (Subject, Header and Body) with Block, Allow, Quarantine, Encrypt, or Do not encrypt actions
  • Attachment Filtering
  • Intent Analysis

The following tools are not applied to outbound mail:

  • IP Reputation, a sender authentication mechanism
  • Sender Policy Framework (SPF), a sender authentication mechanism
  • DomainKeys (DKIM) inspection
  • Exempt/block list

See also:

Outbound Mail Encryption

To prevent data leakage and ensure compliance with financial, healthcare, and other federally regulated agency information policies, you can require all email sent from any or all configured domains to be encrypted by configuring outbound mail encryption policies on the Outbound Settings > Content Policies page at the domain level.

Inbound and outbound email transmission can also be required over a TLS channel.

See also:

Outbound Message Footer

You can configure Barracuda Email Security Service to append a custom text and/or html footer to each outbound message at the global level on the Outbound Settings > Tagline/Footer page.

Appending a footer to outbound messages will cause outbound messages to fail a DKIM check, affecting mail delivery for recipients who check for DKIM.

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