1. From a user account that is a member of the RTCUniversalServerAdmins group (or has equivalent user rights), or is assigned to the CsAdministrator role, log on to any computer in your internal deployment.

2. Open a browser window, and then enter the Admin URL to open the Lync Server Control Panel. For details about the different methods you can use to start Lync Server Control Panel, see Open Lync Server Administrative Tools.

3. In the left navigation bar, click External User Access, click Access Edge Configuration.

4. On the Access Edge Configuration page, click Global, click Edit, and then click Show details.

5. In Edit Access Edge Configuration, under Enable communications with federated users, select or clear the Enable partner domain discovery check box to enable or disable automatic discovery of partner domains.

6. Click Commit.

To enable federated users to collaborate with users in your Lync Server deployment, you must have also configured at least one external access policy to support federated user access. For details, see Enable or Disable Federation and Public IM Connectivity in the Deployment documentation or the Operations documentation. For details about controlling access for specific federated domains, see Manage SIP Federated Domains for Your Organization, Manage SIP Federated Providers for Your Organization and Manage XMPP Federated Partners for Your Organization in the Operations documentation.

Discovery of federation partners can be managed by using Windows PowerShell and the Set-CsAccessEdgeConfiguration cmdlet. This cmdlet can be run either from the Lync Server 2013 Management Shell or from a remote session of Windows PowerShell. For details about using remote Windows PowerShell to connect to Lync Server, see the Lync Server Windows PowerShell blog article "Quick Start: Managing Microsoft Lync Server 2010 Using Remote PowerShell" at http://go.microsoft.com/fwlink/p/?linkId=255876.

To enable discovery of federation partners

To disable discovery of federation partners