Hello all, I have what I hope is an easy question.
We have an existing transport rule that was created to restrict user ability send external e-mail unless they are a member of a specific distribution group. This has been in place for quite sometime and it appears to work if an internal user tries to create and send a message externally. However, it was recently discovered that users can respond to messages received from extenral sources. The rule is setup like this: Sent to users Outside the organization, send <message> with 5.7.1, except when the message is from a member of <distribution group>. Is there a way to prevent replies to messages received from external sources? It would be preferable to leverage the existing group for users who are allowed to send externally. - Sean
