Blocked senders
Email Security marks all messages from these senders with a disposition.
To configure blocked senders:
- Log in to Zero Trust ↗.
 - Select Email Security.
 - Select Settings, go to Detection settings > Blocked senders.
 - On the Detection settings page, select Add a sender.
 - Select the Input method: Choose between Manual input, and Upload blocked sender list:
- Manual input:
- Sender type:
- Email addresses: Must be a valid email.
 - IP addresses: Can only be IPv4. IPv6 and CIDR are invalid entries.
 - Domains: Must be a valid domain.
 - 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 information about the blocked sender policy.
 
 - Sender type:
 - Upload blocked sender list: Upload a file no larger than 150 KB. The file cannot can only contain 
Blocked_SenderandNotesfields. The first row must be a header row. 
 - Manual input:
 - Select Save.
 
To export a list of blocked senders:
- On the Detection settings page, select the blocked senders you want to export.
 - Select Action.
 - Select Export to CSV.
 
To edit a blocked sender:
- On the Detection settings page, select the blocked sender you want to edit.
 - Select the three dots > Edit.
 - Edit the blocked sender.
 - Select Save.
 
To delete a blocked sender:
- On the Detection settings page, select the blocked sender you want to delete.
 - Select the three dots > Delete.
 - On the pop up message, select Delete.
 
To delete multiple blocked senders at once:
- On the Detection settings page, under Blocked senders, select the senders you want to delete.
 - Select Action
 - Select Delete.
 
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