In this post I’ll look at how to configure a postmaster address for our Exchange Organisation.
The postmaster address is used for non-delivery reports (NDRs) sent to recipients outside of your Exchange Organisation and is specified in RFC 2821.
In Exchange 2013 the external postmaster address is blank by default. This has the effect of the external postmaster address being postmaster@YourDefaultAcceptedDomain.
It can be useful to create a postmaster mailbox, or assign the email address to an admin mailbox so that recipients can reply to NDR messages for assistance. Anyone who is familiar with NDRs will appreciate they are far more useful to admins than they are to end users! The downside of this though is as it’s a well known address it can be open to abuse and spam.