Let’s say you have a desktop pool or RDSH Farm. You want to try out something in Horizon that requires a change to the Agent or Client, but you can’t remember if it’s been installed. You could reinstall the agent or client to make sure the component you need is there. But that’s a lot of manual work.
Thanks to a tip from a couple of my colleagues, including William Uhlig and Dan Berkowitz, there is an easier way to see what was installed with the Horizon Agent. You can just check a registry key.
Inside your virtual desktops and RDSH servers, there is a registry key that shows all of the features available in the Horizon agent and whether they are available locally. This registry key is located at HKEY_LOCAL_MACHINE\Software\VMware, Inc.\Installer\Features_HorizonAgent
As you can see in the attached screenshot, features that are available have a value of “Local.” Features that aren’t available, ie those that were not installed, as listed as being “Absent.”
There is also a registry key that shows installed features for the Horizon Client on Windows. Horizon has a single installer that is used for both 32-bit and 64-bit Windows, so the location of this key will depend on what version of Windows you have installed. The path for this registry key on a 64-bit machine is HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\VMware, Inc.\VMware VDM\Client\Installer\.
Inside this registry key, there will be a key named with a GUID. The contents of this field contain the list of features that are installed in the Windows Horizon Client. Unlike the Agent install key, it uses a binary value to denote if a feature is installed instead of “local” or “absent.” The Horizon Client has fewer installable options compared to the agent, and the only optional item that does not appear in this key, at least in a default installation, is URL Content Redirection. This feature require a command-line switch to enable in the Horizon Client installer.