After reading the following article I still fail to get NDR sent to postmaster http://technet.microsoft.com/en-us/library/bb400930(v=exchg.80) We already have an account called postmaster@mydomain.ie So I used the command Set-OrganizationConfig -MicrosoftExchangeRecipientReplyRecipient postmaster command runs successfully. To test this I send an email from an my own account to another email account that I know that mailbox is full. When I send and email from my own email account I get an NDR reply to my account as expected. However, when I login to postmaster account there is no NDR message ? Am I missing something ? Ray