Managing Transport rules and adding disclaimers
Transport Rules offer a very granular control to IT admins over the mail flow in your Exchange organization. It can help to build ethical walls between the groups of users; it can protect messages using Active Directory and/or Azure Rights Management Services to encrypt the content and apply disclaimers to messages.
In the first example, we will see how to restrict two groups of users from talking to each other using Exchange Transport Rules. In this case, we will block the e-mail flow between Sales and Research group members except if the message is coming from Peter Houston or Holly Holt who are heading these two groups. You can use multiple conditions (predicates) to build a rule that meets your organization's requirements:
New-TransportRule "BlockMessagesBetweenResearchAndSales" -BetweenMemberOf1 "Sales_SG" -BetweenMemberOf2 "Research_SG" -ExceptIfFrom "Peter Houston","Holly Holt" -RejectMessageEnhancedStatusCode "5.7.1" -RejectMessageReasonText...