If you do not define phone numbers in +E.164 format for each user in your Active Directory, you must perform other actions to ensure that the numbers in your Active Directory are processed into the communications server address book in a form that Cisco Unified Communications Manager dialing rules can process to dial a number. The communications server is either Microsoft Lync Server or Office Communications Server (OCS).
If all the numbers in your Active Directory are in +E.164 format, you do not need to configure normalization rules for the communications server. This is the easiest way to deploy Cisco UC Integration for Microsoft Lync.
If the numbers in your Active Directory are not in +E.164 format, then you must configure normalization rules to ensure that Microsoft Lync downloads +E.164-formatted numbers from the communications server.
This is necessary because the communications server requires +E.164-formatted numbers, unless you configure normalization rules. For information about this topic, see the following URL: