It sounds like you're referring to AT&T Address Book. Here is a link to information about the address book: http://www.att.com/esupport/article.jsp?sid=KB108796&cv=820,748#fbid=X7WFra0HuMr
As Fred indicated, not all phones are compatible with the AT&T Address Book. You'll need to determine if your phone is compatible by clicking this link and following the steps provided: http://www.att.com/learningcenter/addressbook-phonessupported.do
Please let us know if you need additional information, hope this helps!
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