In order to do, you would create a new email and in the subject line type [ENCRYPT] before typing anything else.
The [ENCRYPT] must be before any RE: or FWD: etc.
Example:
The recipient will receive an email from “noreply@barracuda.com” stating that they received an encrypted message and need to create a password.
Once done, they can see the message. The password will be set for that email address for all future messages.
Example:
If you have any questions, please contact IT