My customer has a Folder in Exchange which has been given email addresses like email@example.com and firstname.lastname@example.org Just this afternoon, hundreds of bounce-backs have been landing in this folder. They are in response to emails that have apparently been sent out from non-existent users on this domain.
I don't understand why the bounce-backs are landing in the Info folder. In Exchange - Global Settings - Message Delivery - Recipient filtering I have ticked the box to filter recipients who are not in the Directory, and Recipient Filtering is turned on in the Default SMTP connector. So how do I fix this?