Forum Discussion
Reject policy for all email that are not a active user
Is there a policy or rule that reject all inbound email that are send to not active users. As a dynamic rule / policy. Or a way to allow emails to active users and the rest reject. It could be a s...
PaulNewell
Microsoft
MicrosoftXenoxNL are you familiar with DBEB/Directory-based Edge Blocking? Messages sent to non-existent addresses within authoritative domains are dropped: Use Directory-Based Edge Blocking to reject messages sent to invalid recipients in Exchange Online.
Additionally, you can always set a recipient (mailboxes, distribution lists, etc.) to require that a sender be "authenticated" (using the -RequireSenderAuthenticationEnabled paramter on the Set-* cmdlets).
Otherwise, you you can always get more granual with your needs by creating transport rules to block external senders to certain recipients/scenarios.