You install the November 2016 Cumulative Update for Microsoft Lync Server 2013. When you search for a user by using Lync Mobile, no results are returned. Additionally, an error entry is logged in the Application event log on the Lync Server that contains the following:
Event ID 20003
Source: LS UCWA
The following file is available for download from the Microsoft Download Center:
Download the Cumulative Update Server Installer update package.
Note Install this update on the server that is running Lync Server 2013.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminology that Microsoft uses to describe software updates.