This article describes an update that enables Microsoft Lync 2010 to display extension numbers in contact cards for contacts that use a non-US telephone number together with an extension number.
To display the extension number in the contact card, the administrator must install the following cumulative update:
2737155 Description of the cumulative update package for Lync 2010: October 2012
After the update is installed, the administrator must set the value of the ShowExtensionInFormattedDisplayString client policy to "true." To do this, the administrator must run the following cmdlets in the Lync Server 2010 Management Shell: