Symptoms
This issue occurs when you start a Microsoft Whiteboard sharing or Microsoft PowerPoint sharing session to a federated user in an instant message conversation in a Microsoft Lync Server 2013-based Lync client.
This issue occurs when an administrator sets a policy to prevent anonymous participants in meetings in your organization. For example, the administrator runs the following command in PowerShell:Set-csconferencingpolicy -AllowAnonyumousParticipantsInMeetings $False -Identity FederationTest When this issue occurs, the federated user will be stuck in the meeting lobby.Resolution
To resolve this issue, install the May 2015 cumulative update for Lync Server 2013 core components.
More Information
This issue occurs because the Lync Server 2013-based Lync client incorrectly sends an INFO message that contains the "<setLobbyAccess><access>granted</access></ setLobbyAccess>" parameter setting, even though the federated user has no access to the meeting lobby.