Ever wonder how Exchange determines the FQDN for the \\.\BackOfficeStorage\<FQDN>\MBX or http://exchangeserver/exadmin/admin/<FQDN>/MBX?  This FQDN just so happens to come from the Default Recipient Policy object in the AD.  This object has the property “gatewayProxy” which contains both an X400 and SMTP address.  The SMTP address portion of this property is used as the FQDN in the above listed paths.

- Chris Ahlers