What is the Microsoft Exchange Recipient in Exchange 2013?

MicrosoftExchange329e71ec88ae4615bbc36ab6ce41109e@your-domain.com or also know as the Microsoft Exchange Recipient is a special recipient object that is used as an internal postmaster to perform options such as sending DSN's, journal reports and error messages.

Within Exchange 2013 I noticed that there was what looked like a routing loop occuring - messages were originating from this address. I noticed there were 1000's of DSN's being generated with the following error in the event information:

"BadmailReason, NDRing a mail recepient that requires a DSN"

Using the Get-OrganizationConfig cmdlet you can verify this:

Get-OrganizationConfig | FL *MicrosoftExchangeRecipientEmailAddresses*

Simply creating the non-existent user stopped the DSN's in their tracks.