Block lists

When you add blocked senders, Cloud 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 Cloud Email Security dashboard Open external link .

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 Open external link . 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