Citrix ICA policies include an option to control if applications are allowed to allocate a virtual channel, which the VDI Zoom Meeting client requires. Zoom uses the virtual channel to connect to the Zoom VDI Plugin on the thin client, in order to provide an optimized Zoom Meeting and Zoom Phone experience.
Starting with Citrix VDA 2109, the default virtual channel allow list policy changed from Disabled (any application can allocate a virtual channel) to Enabled (only Citrix applications and applications added to an exception list are allowed to allocate virtual channels). This change for the virtual channel policy occurs even if you are upgrading an existing installation where you did not change the policy. Additional steps are required to allow Zoom to open a virtual channel.
The easiest way to ensure that Zoom can create and open a virtual channel to connect to the VDI plugin is to set the policy for the virtual channel allow list to disabled. If the policy state was changed to enabled after updating to release 2109, you can edit the policy to return the status to disabled.
Note: If your virtual desktops allow end users to download and install software themselves, we recommend configuring the virtual channel allow list to disabled. Unless the installation default for all users is selected, creating a policy exception based on the application path for all users (provided below) will not apply to individual users.
If you prefer to keep the virtual channel allow list policy configured as enabled, you will need to add the Zoom application to the list of applications that are allowed.
Please refer to the virtual channel allow list policy for more information.