An administrator needs to configure Prism to send encrypted messages to a set of recipients.

The best way for the administrator to configure Prism to send encrypted messages to a set of recipients is to set the SMTP Security Mode to STARTTLS. This will ensure that all messages sent over SMTP are encrypted and secure. Additionally, the administrator should consider installing SSL certificates on Prism Central to ensure that the messages are being sent securely. Finally, the administrator should consider configuring Prism Central to use Cluster Lockdown, which will help ensure that the messages are only sent to the intended recipients.