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Block lists

When you add blocked senders, Email Security automatically marks all messages from these senders with a MALICIOUS disposition.

Add a blocked sender

To create a new blocked pattern:

  1. Log in to the Email Security dashboard ↗.

  2. Go to Settings (the gear icon).

  3. On Email Configuration, go to Block List > Blocked Senders.

  4. Select + New Sender.

  5. Enter the pattern information:

    • Sender: Enter one of the following types of pattern:

      • Email addresses: Must be a valid email.
      • IP addresses: Can only be IPv4. IPv6 and CIDR are invalid entries.
      • Regular expressions: Must be valid Java expressions ↗. Regular expressions are matched with fields related to the sender email address (envelope from, header from, reply-to), the originating IP address, and the server name for the email.

    • Notes: Provide additional notes about the blocked sender pattern.

  6. Select Save.

CSV uploads

You can also upload a CSV file of multiple allowed patterns. The CSV file must be smaller than 150 KB, start with a header row of all required values, and contain no additional fields.

An example file would look like this:

Blocked_Sender, Notes
john.smith@email.com, John Smith
melanie.turner@email.com, Melanie Turner