Summary: To ensure Microsoft Teams is optimized in ICA when connecting to the Remote PC, but is un-optimized when a user is using the VDA directly outside of Citrix.

Scenario: Users (the same user in same VDA) connect to their sessions in two ways:

• Citrix Remote PC ICA session while working remotely

• Accessing the VDA physically while working in the office

How to achieve:

• Citrix Remote PC ICA session: MS Teams optimization should start

• Physical access: MS Teams optimization shouldn't start 

Instructions

Enabling optimization for Citrix ICA session:  As per the guide at https://docs.citrix.com/en-us/citrix-virtual-apps-desktops/multimedia/opt-ms-teams.html#enable-optimization-of-microsoft-teams configure optimization via Citrix Policy in Studio.
• This will set MSTeamsRedirSupport under HKEY_CURRENT_USER\Software\Citrix\HDXMediaStream to 1 –enabling optimization
• Optimization for Microsoft Teams requires a minimum of Microsoft Teams version 1.2.00.31357

For Direct/Physical Access of the VDA(No optimization for Remote PC / Outside of Citrix ICA): There would be no action needed because if you are not in Citrix ICA, Teams will display “VDI mode - Not optimized”.  This is due to Teams detecting that the VDA is installed on the RemotePC and Teams is aware that it's not operating in an ICA session. 

Note: You will have to exit and re-connect to teams once you switch from ICA to Direct access and Vice versa to re-initiate the MS Teams connection to optimize and unoptimize MS Teams session as per the protocol.