NDR sent to internal users of List Server
Issue encountered
Internal users receive a non-delivery report when sending emails to list server. This issue typically occurs when GFI MailEssentials is installed on a Gateway machine.
Cause
The list server email address does not exist in the Microsoft Exchange store, and thus, internal messages generate an NDR.
Solution
For more information how to use the List Server feature if GFI MailEssentials is installed on a gateway refer to: