Hi Steve! > 3. What difference does it make, whether the clients know the be server name. That is a big problem. Suppose that you have many Back-End-Server, BE1,BE2,BE3,.... Suppose that you want to migrate the mailboxes of 2.000 persons from BE1 to BE2. In this case you must change all mail server name on Outlook client computers from BE1 to BE2. If these mailbox users are overall in the world you must support them per phone / e-mail or with other methods. Can you imagine what a big touble you can have? I think you can imagine that. FE/BE, Microsoft Support told, is developed NOT for RPC over HTTPS, but for OWA. You know, OWA has not all features of full Outlook. Perhaps, you understand now why it is bad if the clients must use BE name in the Outlook profile. Best Regards Mustafa