Spammers often use the trick of sending password encrypted archives in the hope to bypass some filters, and saying the “password” in the body of the spam message. These messages can be blocked by enabling the “Block Password Protected Attachments” feature. By default, the function will be auto enable.
- In the Domain Level Control Panel, select Incoming - Protection Settings > Attachment Restrictions. Remember to untick that "Block password-protected archive attachments" option.
- Remember to click "Save" and this function will be unable successfully.