The Media Optimization for Microsoft Teams feature redirects audio calls, video calls, and viewing desktop shares for a seamless experience between the client system and the remote session without negatively affecting the virtual infrastructure and overloading the network. Microsoft Teams media processing takes place on the client machine instead of in the virtual desktop and does not rely on Real-Time Audio-Video (RTAV).

Media Optimization for Microsoft Teams Features

Important: For details on required Horizon Client versions, Horizon Agent versions, and Teams client versions for each feature see VMware Knowledge Base article 86475.

Media Optimization for Microsoft Teams offers the following features:

  • Accepting and making audio and video calls
  • Multiparty audio and video conferencing
  • Transfer, forward, mute, hold, and resume a call
  • PSTN calls using a dial pad
  • Desktop screen sharing
  • Multi monitor screen sharing and screen picker for screen sharing
  • Screen sharing in VDI and RDSH desktop sessions (Windows, Mac, Linux, Chrome, and HTML Access clients)
  • Screen sharing in RDSH published application sessions (Windows, Mac, and Linux clients)
  • Individual application sharing in VDI and RDSH desktop sessions for VMware Blast display protocol (Windows clients)
  • Give and take control of individual application sharing in VDI and RDSH desktop sessions for VMware Blast display protocol (Windows clients). Overlapping applications obscuring the content of the shared application appear greyed out over the shared application.
  • Volume control from the remote desktop
  • Secondary ringer
  • Active speaker identification
  • Live Captions for 1:1 and Team Meetings
  • Custom Together Mode Scenes
  • E911 and Location-Based Routing (Windows and Mac clients only)
  • WebRTC 1.0
  • Give control of screen sharing in VDI and RDSH desktop sessions (Windows, Mac, and Linux clients)
  • Request/take control of screen sharing in VDI and RDSH desktop sessions (Windows, Mac, Linux, Chrome, and HTML Access clients)
  • Request/take control of screen sharing in RDSH published application sessions (Windows, Mac, and Linux clients)
  • Multi Window and Pop-out chat
  • HID Headset controls for Windows and Linux clients*
  • Background Blur and Effects (Windows, Mac, and Linux clients)*
  • Custom background image for Windows clients
  • Simulcast support, which enables multiple video call streams at the same time in meetings, allowing better experience with low network quality (Windows, Mac, and Linux clients)*
In addition, Microsoft supports the following features. Contact Microsoft for any issues with these Microsoft Teams features:
  • Gallery View (2x2)
  • Large Gallery (7x7)
  • Together Mode
  • Call Queue
  • Live Webinar (optimized)
  • Call Quality Dashboard
  • Transcription Support
  • Spotlight
  • Camera can be on while screensharing (Horizon 2106 or later)*
Attention: Features marked with an asterisk (*) will only become available as Microsoft Teams updates are released. Check the Microsoft 365 roadmap to see when each feature will be activated by Microsoft.
For other Microsoft Teams features supported with VDI, see the Microsoft documentation Meetings and live events.
Note: If Microsoft Teams is optimized on a virtual desktop and you encounter generic issues or certain features missing, check the Microsoft Teams web client for the same behavior. Media Optimization for Microsoft Teams on virtual desktops is based on Microsoft Teams web client that leverages WebRTC technology. If you see the same behavior on the web client, contact Microsoft for assistance.

Media Optimization for Microsoft Teams System Requirements

The Media Optimization for Microsoft Teams supports these configurations.
Table 1. Media Optimization for Microsoft Teams System Requirements
System Requirements
Microsoft Server Microsoft 365
Microsoft Teams Client (Optimized)
  • Microsoft Teams Desktop Client x64
  • Microsoft Teams Desktop Client x86
See the Microsoft documentation for installation instructions.
Note: Microsoft Teams web client is not supported with Teams Optimization Pack. Web browser media offload is supported with Browser Redirection. See Configuring Browser Content Redirection for supported browsers and clients. Consult Microsoft documentation for supported browsers for Microsoft Teams web client.
Virtual desktop operating systems Minimum requirement is 2 vCPU for operating systems supported for Horizon Agent.
Client machine operating systems Minimum hardware requirement is 2.4 GHz dual core.

Windows: Media Optimization for Microsoft Teams with Windows client is supported with Horizon Client 2006 and later for VDI desktops, and Horizon Client 2012 and later for RDSH remote desktops and Microsoft Teams as a published application.

Mac: Media Optimization for Microsoft Teams with Mac client is supported with Horizon Client 2103 and later. Starting from Horizon Client 2209, this feature is supported on M1-based Macs as well as 64-bit Intel-based Macs.

Linux: Media Optimization for Microsoft Teams with Linux client is supported with Horizon Client 2106 and later.

Chromebook: Media Optimization for Microsoft Teams with Chromebook client is supported with Horizon Client 2111 and later. To use Media Optimization for Microsoft Teams with Chromebook, Settings > Enable Media Optimization for Microsoft Teams must be enabled. This setting is enabled by default with Horizon Client 2203 and later.

For more information see "Configure Media Optimization for Microsoft Teams in Horizon Client for Chrome" in the Horizon Client for Chrome Guide.

HTML Access: Media Optimization for Microsoft Teams supports the HTML Access Web client running in a Chrome or Microsoft Edge browser. Media Optimization for Microsoft Teams is supported with HTML Access Web client 2111 and later. To use Media Optimization for Microsoft Teams with Chrome or Edge, Settings > Enable Media Optimization for Microsoft Teams needs to be enabled. This setting is enabled by default with HTML Access Web client 2203 and later.

For more information see "Configure Media Optimization for Microsoft Teams in HTML Access" in the Horizon HTML Access Guide .

Deployments

On-premises and cloud:

  • VDI
  • Non-persistent desktops
  • RDS published desktop deployments
  • RDS published application deployments (not supported with versions prior to Horizon Client 2012 or Horizon Client 5.5)

Cloud: Windows 10 Enterprise multi-session and all deployment types for Horizon Cloud Services on Azure.

Display Protocols VMware Blast and PCoIP (no RDP)
TCP Port 9427
Network IPv4
Microphones and Webcams Same devices that are qualified to work with Microsoft Teams
Audio codecs For details, see https://developer.mozilla.org/en-US/docs/Web/Media/Formats/WebRTC_codecs.
  • SILK
  • Opus
  • G.722
Video codecs For details, see https://developer.mozilla.org/en-US/docs/Web/Media/Formats/WebRTC_codecs.
  • AVC/H.264
  • VP8
  • VP9
Media Feature Pack Must be installed on the remote desktop for Windows 10 N and KN versions. You can install Media Feature from the Microsoft download page: https://www.microsoft.com/en-us/download/details.aspx?id=48231.

Installing and Configuring Media Optimization for Microsoft Teams

The Media Optimization for Microsoft Teams feature is installed by default with Horizon Client for Mac, Horizon Client for Linux, Horizon Client for Windows, and Horizon Client for Chrome. For Horizon Client for Windows, end users can deactivate Media Optimization using the client settings.

To use the Media Optimization for Microsoft Teams feature with Horizon Client for Chrome or the HTML Access Web client, the Enable WebRTC Redirection option must be activated in the client settings. To use screen-sharing capabilities with these clients, the Enable screen sharing for Microsoft Teams virtualization option must be activated in the client settings. Both the Enable WebRTC Redirection and Enable screensharing for Microsoft Teams virtualization options are activated by default.

Horizon Agent must be installed before you install Microsoft Teams. If you install Microsoft Teams before installing Horizon Agent, delete the %APPDATA%\Microsoft\Teams folder and relaunch Microsoft Teams.

To use this feature, the Media Optimization for Microsoft Teams group policy setting must be activated. See "VMware WebRTC Redirection Features Settings" in VMware HTML5 Feature Policy Settings.
Note: Starting with the 2212 release, Media Optimization is enabled if the group policy is not configured. If upgrading from an older version of Horizon Agent to the 2212 version, the policy is overridden and enabled. For details on how to deactivate this policy, see "VMware WebRTC Redirection Features Settings" in VMware HTML5 Feature Policy Settings.

See the Microsoft documentation Teams for Virtualized Desktop Infrastructure for installation, setup, and deployment requirements, guidelines on persistent and non-persistent desktops, and limitations of using Microsoft Teams in a remote desktop.

Microsoft updates their Teams recommended version periodically. Check Microsoft for updates and install the latest recommended version to access new features without updating Horizon Client or Horizon Agent.

For more information about installing and configuring Media Optimization for Microsoft Teams, see the TechZone article Microsoft Teams Optimization with VMware Horizon.

Note: Media optimization for Microsoft Teams is not supported in Horizon Agent 7.12 or earlier and Horizon Client versions 5.4.3, 5.4.2, 5.4.1, 5.4, and 5.3 or earlier due to UX issues. These UX issues have been fixed in the latest release of Horizon Agent and Horizon Client.

Pairing Modes for a Session

A user can check if Microsoft Teams is running in optimized mode, fallback mode, or natively in the virtual desktop (no optimization). On the top right corner of the Microsoft Teams interface, click the user icon and navigate to About->Version to see a banner under the user icon describing the Microsoft Teams version and pairing modes:

  • Optimized: If the banner shows VMware Media Optimized, then Microsoft Teams is running in the optimized mode. In this mode, the Enable Media Optimization for Microsoft Teams GPO is activated, Microsoft Teams is running in the virtual desktop, and audio and video is offloaded to the client machine.
  • Fallback: If the banner shows VMware Media Not Connected, then Microsoft Teams is running in fallback mode. In this mode, the Enable Media Optimization for Microsoft Teams GPO is activated and Microsoft Teams has tried to start in Optimized mode, but the Horizon Client being used does not support Microsoft Teams optimization. RTAV is used and audio and video from Microsoft Teams is not offloaded to the client machine. Fallback mode has the same limitations as Optimized mode. When you make a call in fallback mode, you see a warning sign on the call:

    Your device does not support VMware optimization. Audio and video quality may be reduced. Talk to your IT admin.

  • No Optimization: If the banner does not show VMware text in the message, the Enable Media Optimization for Microsoft Teams GPO is not activated. RTAV is used and audio and video from Microsoft Teams is not offloaded to the client machine.

Windows Registry Settings for Background Blur and Effects

Background blur and effects allow users to blur their background or select an available background image before or during a video call or meeting. Administrators can also provide a folder of custom background images for users to apply from as part of a company mandate.

Setting custom background images is only supported for Windows clients.

The windows registry keys allow for the user to specify a custom image selection and to toggle between using custom background images and Microsoft-provided images. The custom background image is applied in the same manner as Microsoft stock images and persist for as long as the registry values are unchanged. The user can switch between custom backgrounds or the Microsoft backgrounds from Teams UI based on the registry values and also choose between different custom images from a designated folder.

There are two registry values in the user level registry key HKCU\Software\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground:
  • enable (REG_DWORD)
  • imageName (REG_SZ)
The following registry values can exist in the administrator level registry key HKLM\Software\Policies\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground:
  • enable (REG_DWORD)
  • defaultImageName (REG_SZ)
  • imageFolder (REG_SZ)

To set the registry key for a user in the Windows registry, navigate to HKCU\Software\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground\enable and set the value to 1 to enable custom image or 0 to disable custom image and select image from Teams UI. The default value is 0.

To specify an image, edit the value HKCU\Software\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground\imageName and enter the image name with .png or .jpg suffix.

Administrators can upload custom background images to a designated folder that users can apply during video calls and meetings. The administrator level setting overrides the user level setting.

To set the registry value at an administrator level, you must access the Windows registry as administrator. Navigate to HKLM\Software\Policies\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground\enable and set the value to 1 to override user settings and always select custom image as the background or 0 to override user settings and always select image from Teams UI. When the enable registry value is not present, the user settings are honored and users can switch between applying custom background images or the images from Teams UI at their own discretion. If administrators do not want to force override user settings, they must not add the enable value or they must delete it if it is present.

To specify a default custom image, edit the value HKLM\Software\Policies\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground\defaultImageName and enter the image name with .png or .jpg suffix. This custom image takes effect when the user does not select any custom image or selects an incorrect or unsupported image. By default, all custom images are located in the folder C:\Program Files\Common Files\VMware\Remote Experience\x64\MSTeamsBackgroundImages, but the admin can configure a specific folder by setting this registry key in HKLM\Software\Policies\VMware, Inc.\VMware WebRTCRedir\MSTeamsCustomImagesBackground\imageFolder

HID Headset Support

HID (Human Interface Device) usage is supported on Windows and Linux client endpoints.

We support:
  • Volume up and down
  • Mute/unmute button
  • Call accept and reject
We do not support:
  • Hold/Resume

E911 and Location-Based Routing

This feature is supported for Windows and Mac clients only.

To support Dynamic E911 for Horizon Client, you must activate OS location services for the client application. See Configuring E911 Services for Microsoft Teams in the Horizon Client for Windows Guide and Horizon Client for Mac Guide. Static E911 does not need location services to be activated.

The Enable E911 for Microsoft Teams group policy setting must be activated or not configured to use the feature. See VMware WebRTC Redirection Features in VMware HTML5 Feature Policy Settings.

Limitations of Media Optimization for Microsoft Teams With All Clients

Media Optimization for Microsoft Teams has the following limitations for all supported client platforms. Contact Microsoft for Microsoft limitations.
Limitation Comments
The camera light stays on if the user puts the video call on hold (but video is not sent). Microsoft limitation
Microsoft Teams running in fallback mode on an RDSH machine cannot access the remote machine’s microphone and speaker. See the KB article https://kb.vmware.com/s/article/84205 for a workaround.
VDI participants cannot create breakout rooms but can join only. Microsoft limitation
Live Events is not optimized, but supported as an attendee. Producer and presenter roles are not supported for a VDI user. Microsoft limitation. As a workaround, use Live Events (Web) client with browser content redirection. See https://kb.vmware.com/s/article/88274 for details.
Media bypass for direct routing is not supported. Microsoft limitation
1080p video is not supported. Microsoft limitation
Zoom in and out function in Microsoft Teams is not supported. Microsoft limitation
Microsoft starts meetings with a lower resolution and gradually increases the resolution based on network conditions, such as bandwidth of meeting participants and video window size. Microsoft limitation
Quality of Service (QoS) in Microsoft Teams is not supported. Microsoft and VMware limitation
Test Call button is not available. Microsoft limitation
3x3 video gallery is not supported. Microsoft limitation
Give control while screen sharing is not supported if Teams is an RDSH Application. VMware and Microsoft limitation
When screenshare is being controlled by a peer, the cursor sometimes moves to the last location of the controller. VDI limitation
In the sharing toolbar, the Give Control toolbar only shows two participants at a time. To scroll to other participants, use the up/down arrow keys. Microsoft Limitation.
When screen sharing, the sharing toolbar might be hidden under the Horizon Client toolbar when Horizon Client is in full screen. To access the Microsoft Teams sharing toolbar, do one of the following:
  • Hide the Horizon Client toolbar.
  • Exit Horizon Client Fullscreen (use Horizon Client in window mode).
  • Drag the floating Horizon Client toolbar to another location.
Shared system audio/computer sound is not supported while screensharing. Microsoft Limitation
For a list of other Microsoft Teams limitations on VDI, see the Microsoft documentation Meetings and live events.

Limitations of Media Optimization for Microsoft Teams With Specific Clients

Media Optimization for Microsoft Teams has the following limitations for certain client platforms.
Limitation Comments
Outgoing individual application window sharing is not supported for Mac and Linux clients. VMware limitation
Outgoing individual application window sharing is not supported for PCoIP display protocol (Windows Client). VMware limitation
Outgoing individual application window sharing is not supported for Microsoft Teams as a published application. VMware limitation
Give control of shared individual application window is not supported (Windows Client). VMware limitation
HID:

For Windows and Linux client end points, hold and resume are not supported.

Microsoft limitation
Background Blur and Effects:
  • For non-Windows clients, custom backgrounds are not supported.
  • Tenant-based background images configured by IT admins and are not supported on any clients.
Microsoft limitation
Media Optimization on Linux and Mac clients does not support proxy configuration. VMware limitation

The following screen-sharing limitations apply to the Chrome client and HTML Access Web client:

  • Content in the screen-sharing window turns black when the window is minimized.
  • The mouse cursor disappears when a native client window moves in front of the screen-sharing window.
  • Screen-sharing content disappears when the user locks and then unlocks the client operating system.
VMware limitations
The following screen-sharing limitations apply to the Chrome client and HTML Access Web client:
  • When a user shares all or part of their screen, the shared area is not surrounded by a red outline as expected.
  • When a user selects an option in the "Share your screen" dialog box other than the specific browser tab being used by the client, that user can inadvertently share their local desktop.
Google limitations
On the HTML Access Web client, Media Optimization becomes unavailable when the browser page is refreshed. To use Media Optimization after a page refresh, restart Microsoft Teams on the remote desktop. VMware limitation
Media Optimization does not support multiple-monitor configurations with the Chrome client and HTML Access Web client. VMware limitation
Media Optimization is not supported on the Chrome client and HTML Access Web client if Microsoft Teams is published as an application. VMware limitation
If you activate or deactivate location sharing to support the E911 feature using the VDI client or agent GPO policy, the cached E911 location status continues to display on the VDI Teams call page until Teams is restarted on the VDI desktop. VMware limitation
In both native and VDI Teams, locations shown by the E911 feature might not match those shown in Google Maps. Microsoft limitation
Due to a Microsoft issue, if you log out and then back into either native or VDI Teams, there can be a delay of up to two minutes before the emergency location of the client device is displayed by the E911 feature. Microsoft limitation

Knowledge Base Articles Related to Media Optimization for Microsoft Teams

For Knowledge Base articles related to Media Optimization for Microsoft Teams, search “HorizonTeamsOptimization” in VMware Knowledge Base or go to https://kb.vmware.com/s/global-search/%40uri#q=HorizonTeamsOptimization.

For details on required Horizon Client versions, Horizon Agent versions, and Teams client versions for each feature see VMware Knowledge Base article 86475.

See the Microsoft documentation Teams for Virtualized Desktop Infrastructure for installation, setup, and deployment requirements, guidelines on persistent and non-persistent desktops, and limitations of using Microsoft Teams in a remote desktop.

Microsoft updates their Teams recommended version periodically. Check Microsoft for updates and install the latest recommended version Horizon Client or Horizon Agent.

For more information about installing and configuring Media Optimization for Microsoft Teams, see the TechZone article Microsoft Teams Optimization with VMware Horizon