We are normally asked on the Microsoft Exchange 2010 Social Forum.

When should we be using Subscriber Access Number and When should we be using Auto Attendant.

We can call Subscriber Access Number to access the caller’s own Exchange mailbox via Outlook Voice Access or leave a voice mail to other Exchange users.

As to Auto Attendant, it can be used to guide the caller to locate different departments/locations of a company. For example, a company has many departments, such as finance, HR, IT and etc. Then, you can configure the Auto Attendant to guide the caller with a customized greeting, like “To contact finance department, please press 1. To contact IT department, please press 2.” In this way, the caller does not need to remember the extension of each department while the Auto Attendant can guide the caller.

Now let us take an example, the Subscriber Access Number set on the Dial Plan is 2000 and the Pilot Identifier set on Auto Attendant is 3000. When a caller calls 2000, the Subscriber Access Number serves and the caller will hear “Welcome to Microsoft Exchange …”. However, if  caller calls 3000, the Auto Attendant serves. The caller will hear “Welcome to Microsoft Exchange Auto Attendant …”.


Here is a Nice Diagram which gets you going on Subscriber Access part.