Product Documentation

Support for Microsoft VDI Plug-in for Skype for Business

Feb 04, 2016

XenApp 6.x, XenApp 7.x, XenDesktop 7.x, and Citrix Receiver 4.x include the interfaces required for compatibility with Microsoft’s VDI Plug-in for Skype for Business.

The Microsoft Skype for Business "universal communications" client provides features such as Instant Messaging (IM), voice chat, desktop video conferencing, telephony, app sharing and screen sharing. Citrix supports multiple methods of delivering the Skype for Business clients from XenApp and XenDesktop. The primary methods are:

  • HDX RealTime Optimization Pack
  • Microsoft VDI Plug-in for Windows
  • Generic HDX RealTime technologies

The Microsoft VDI Plug-in packages the Skype for Business media engine as a headless plug-in to the Citrix Receiver for Windows. The VDI Plug-in is suitable for customers using Skype for Business 2015 exclusively with Windows devices (limited to Windows 7, WES 7 and Windows 8.x) and delivering the Skype for Business client as part of a full virtual desktop. For organizations with Linux thin clients or Apple Mac computers, Citrix recommends the HDX RealTime Optimization Pack, which optimizes the delivery of the Skype for Business client to Windows, Mac OS X and Linux devices. For Windows users, the primary advantage of the VDI Plug-in is that the user interface and feature set is closer to that of native Skype for Business, whereas the HDX RealTime Optimization pack introduces some UI changes due to limitations of the current Microsoft APIs. For a comparison of the methods of delivering the Skype for Business client, see CTX200279 - Skype-Lync Delivery Feature Matrix.

This article describes how to install the Microsoft VDI Plug-in. This article also provides a list of known issues. For feature limitations of the VDI Plug-in, refer to Known Limitations for VDI on the Microsoft TechNet site.

Overview of the Microsoft VDI Plug-in

The Microsoft VDI Plug-in (media engine) for Windows optimizes Skype for Business audio and video in a virtual desktop environment. It is designed as a plug-in to Citrix Receiver for Windows. The VDI Plug-in enables Windows device users to make audio and video calls while preserving server scalability by offloading media processing to the user device. It provides an alternative to the Citrix HDX RealTime Media Engine plug-in, a component of the HDX RealTime Optimization Pack. (The VDI Plug-in media engine and the HDX RealTime Media Engine are mutually exclusive per device.)
Citrix supports the following deployments with the Microsoft VDI Plug-in:

  • XenDesktop 7.x deployment of Windows 7 and Windows 8.1 Desktop OS machines
  • XenDesktop 7.x deployment of Windows Server 2008 R2 machines with hosted Remote Desktop dervice (RDS) desktops
  • XenDesktop 5.6 deployment with XenDesktop 7 VDI VDAs
  • XenApp 6.x deployment of Windows Server 2008 R2 published desktops
  • XenApp 7.x deployment of Windows Server 2008 R2 published desktops
  • VDI-in-a-Box 5.4 (XenDesktop 7.1 VDA) deployment of Windows 7 Desktop OS machines

If using the Microsoft VDI Plug-in, the Skype for Business 2015 client must be delivered as part of a full virtual desktop. Unlike the HDX RealTime Optimization Pack, the VDI Plug-in does not support delivery of the Skype for Business client as a XenApp published/seamless application.

The following combination of software has been formally qualified by Microsoft as noted in Microsoft TechCenter Infrastructure qualified for Microsoft Lync and represents the minimum versions that should be used with the VDI Plug-in:

  • XenDesktop VDI Virtual Delivery Agent 7.1
  • Citrix Receiver 4.1.02 for Windows
  • Virtual desktop OS: Windows 7 with Service Pack 1
  • Endpoint OS: Windows 7 with Service Pack 1 or Windows Embedded Standard 7 with Service Pack 1

Citrix recommends using the latest available version of Citrix Receiver for Windows.

On XenApp 7.1/7.5 and XenDesktop 7.1/7.5, Citrix recommends applying hotfix ICAWS750WX64029 (not required with XenApp/XenDesktop 7.6). For the list of issues resolved in this hotfix, refer to CTX140257 - Hotfix ICAWS750WX64029 - For VDA Core Services 7.1/7.5 for Windows Desktop OS (64-bit) - English

System Requirements

  • Skype for Business Server 2015 configured with EnableMediaRedirection set to True.
  • 32-bit Microsoft VDI Plug-in installed on a Windows device running a supported version of Windows; for Microsoft VDI Plug-in installation requirements see VDI Plug-in Prerequisites. Citrix Receiver for Windows requires the 32-bit version of the Microsoft VDI Plug-in on the device, even on a 64-bit Windows machine. The 64-bit version is not compatible with Citrix Receiver for Windows since the bitness of the VDI Plug-in must match the bitness of Receiver.
  • A Skype for Business certificate installed on the user device as well as on the XenApp or XenDesktop server.

Note: When installing Microsoft Office locally on the device, you must use the 32-bit version of Office.

Install the Microsoft Lync VDI Plug-in

  1. Download the latest release of Citrix Receiver for Windows (minimum Citrix Receiver 4.1.02) and install it on the user device.

  2. Download the Microsoft VDI Plug-in (32-bit) from the Microsoft Download Center.

  3. Install the VDI Plug-in on the device. See Deploying the Lync VDI Plug-in
    Note: Be sure to install the latest Microsoft updates.

  4. Install the Microsoft Skype for Business server certificate on the device. 

Validate the Skype for Business configuration

The recommended best practice is to use the Microsoft RDP client first to validate your Skype for Business configuration independent of any Citrix software, and then switch to Citrix Receiver. When you validate your configuration with the Microsoft RDP client, the bit version of the Microsoft VDI Plug-in must match that of the RDP client and the Windows operating system, as described in Lync VDI Plug-in Prerequisites.

If you perform verification on a 64-bit Windows OS, substitute the 32-bit version of the Microsoft VDI Plug-in when you switch from RDP to ICA and the Citrix Receiver for Windows.

To validate proper pairing of the VDI Plug-in
When Skype for Business and the VDI Plug-in have paired correctly, the icon under the Contacts list includes a green checkbox and the Audio Device settings appear as displayed in the following screen shot:

NEED NEW SCREENSHOT

User-added image

As noted on the above screen, audio device tuning is not supported when using the VDI Plug-in.

Troubleshooting

Issues Pairing the Skype/Lync client with the VDI Plug-in

When Skype for Business and the VDI Plug-in are not paired correctly, the icon under the Contacts list does not include the green checkbox and the Audio Device settings show the remote devices as displayed in the following screen shot: 

NEED NEW SCREENSHOT

User-added image

 

If Microsoft Skype for Business client has trouble pairing with the VDI Plug-in:

  • Restart the device.
  • Make sure the endpoint operating system is 32-bit and has the 32-bit VDI plug-in installed, not the 64-bit version.
  • Make sure there is an exception on the Windows firewall for the Skype for Business ports (or disable the firewall). Do this on both the endpoint and VDA. The list of ports used by Skype for Business is here: http://technet.microsoft.com/en-us/library/gg398833.aspx.
    Ensure that any routers between the endpoints, VDAs, and Skype for Business server are not blocking the port; the endpoints and VDAs both must be able to reach the Skype for Business server.
  • Ensure that the EnableMediaRedirection policy is set to True on the Skype for Business server (see http://technet.microsoft.com/en-us/library/jj205154.aspx).  
  • Make sure that the latest Skype for Business updates from Microsoft have been installed.
    • The file version for c:\Program Files\Microsoft Office\Office15\LyncVdiPlugin.dll on the endpoint must be at least 15.0.4517.1504
    • The file version for c:\Program Files\Microsoft Office\Office15\Lync.exe on the VDA must be at least 15.0.4517.1504
  • Ensure that an audio/video device is plugged into the endpoint.
  • After establishing a connection to the VDA, use a tool such as Process Explorer to verify that LyncVdiPlugin.dll is loaded by the wfica32.exe process. You can find Process Explorer here: http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx. To check if the DLL is loaded, on the menu, go to Find, and then Find Handle or DLL.

For more information about troubleshooting the Microsoft VDI Plug-in, see Troubleshooting the VDI Plug-in.

Log Locations

To capture Skype for Business logs, complete the following:

  1. In the Skype for Business main window, go to Tools > Options > General.

  2. For Logging on to LySkype for Business, choose Full.

  3. Select the check box for Also turn on Windows Event logging for Lync to collect troubleshooting information.

  4. Collect the logs from the following locations:

  • On the Skype for Business server: %localappdata%\Microsoft\Office\15.0\Lync\Tracing

  • On the device: %localappdata%\Microsoft\Office\15.0\Lync\Tracing

To capture logs for the Virtual Delivery Agent (VDA), complete the following:

  1. Use CTX130147 - Citrix Scout to run a CDF trace with XenDesktop 7. The relevant trace modules for the VDA are:

  • MF_DLL_CtxDvcApi

  • MF_Driver_CtxDVC

  • MF_Driver_Wdica

  1. Upload the trace file to Citrix Insight Services.

  2. Review the trace on the Citrix Insight Services site.

Known issues

When right-clicking on a voice message in Lync 2013 and selecting Play, the message cannot be heard.

Workaround: Double-click on the voice message or click on the View More in Outlook link to open the voice message in Outlook; this enables the message to be heard through the speakers on the user device. 

Alternatively, if you select this icon

User-added image

 and choose Call Voice Mail, you can listen to the voice message through your USB headset.

Third-party Issues

Check directly with Microsoft for updates regarding the following issues:

  • When a call starts, the audio volume on the device is reduced. Use the device audio controls to increase the volume.
  • The camera is activated when the user hovers the mouse over the video preview if the camera is present on the "server side" (host) computer (physically or virtually). Preview is shown, despite text on the screen that says video preview is not supported. Video fails to start for the rest of the call if the video preview was shown. The issue does not occur if a video call is started by right-clicking a contact and selecting Make video call or by using the Meet Now dialog. This issue is caused by Skype for Business, when paired with the VDI plug-in, still loads any webcam devices present on the [virtual] desktop. Therefore, the virtual webcam device provided by generic HDX Webcam Video Compression is loaded, locking the webcam and preventing Skype for Business from using it. A possible workaround is to disable generic HDX Webcam Video Compression, which is turned on by default. Do this by configuring a policy on the Desktop Delivery Controller (DDC). The policy is under Multimedia Settings and is called Multimedia Conferencing. It is a machine-wide policy. The drawback to disabling generic HDX Webcam Video Compression is that users of other video conferencing applications, such as Citrix GoToMeeting, or users who do not have the VDI plug-in installed, are not able to use their webcam in a XenApp or XenDesktop session.

For feature limitations of the VDI Plug-in, refer to Known Limitations for VDI on the Microsoft TechNet site. The VDI Plug-in is not supported on Windows Thin PC, Windows XPe, WES 2009 or Windows Server 2012 R2. The VDI Plug-in does not support smart card authentication and users must enter their credentials manually if their device is not domain-joined. And the VDI Plug-in solution does not support delivery of the Skype/Lync client as a seamless/published application.