Trident has various security protocols in place to filter out emails containing malicious content. In Zoho Mail web settings, admins can set trusted domains and senders and use additional spam controls to prevent malicious emails from reaching an organization's inbox.

If organization members receive emails from other domains that haven't been filtered by administrators in the spam controls, Trident displays a warning to prompt users to exercise extra caution in their email correspondence. These alerts are shown in the following circumstances:

• Sending and receiving emails from people outside an organization
  

• Receiving emails from unverified domains or senders

• Receiving emails from a new email address for the first time
  

• Receiving emails with suspicious URLs
  

If the emails are not harmful, users can trust the sender to allow future emails. If users find these emails are spam, they can mark them as spam and block all future emails from the sender.

Note: When you block an email, it will move the current email to spam, and all future emails from that sender will bounce back to them.