Admins can create and configure Microsoft Purview Data Loss Prevention policies and Outlook for Microsoft 365 to show pop-up messages that can warn users that the email that they are attempting to send contains sensitive information before the email is sent. Admins can ask them users to provide justification why they are sending an email, or prevent them from sending an email. Below is a sample of how the oversharing configuration can be used to capture the justification from the user before allowing them to send the message. If you're using Group Policy, make sure you've downloaded the most recent version of Group Policy Administrative Template files for Microsoft 365 Apps for enterprise and navigate to this setting from User Configuration/Administrative Templates/Microsoft Office 2016/Security Settings. Check before send and do not allow sending until policy evaluation is completed: Message is checked when the user hits send, but the message will not be sent until all policies are evaluated. Enabled - The message is checked when the user hits send. The administrator needs to configure the time interval after which the user is allowed to send the mail even when evaluation is not completed.
--------------------
Read more at https://bit.ly/3pCzUZI
Source: Microsoft Tech Community Microsoft 365 Blog
