HDX provides a high-definition user experience on any device, at any location. The articles in the Devices section describe these devices:

Optimized vs. generic USB device

An optimized USB device is one for which Citrix Workspace app has specific support. For example, the ability to redirect webcams using the HDX Multimedia virtual channel. A generic device is a USB device for which there is no specific support in Citrix Workspace app.

By default, generic USB redirection can’t redirect USB devices with optimized virtual channel support unless put into Generic mode.

In general, you get better performance for USB devices in Optimized mode than in Generic mode. However, there are cases where a USB device doesn’t have full functionality in Optimized mode. It might be necessary to switch to Generic mode to gain full access to its features.

With USB mass storage devices, you can use either client drive mapping or generic USB redirection, or both, controlled by Citrix polices. The main differences are:

If both generic USB redirection and the client drive mapping policies are enabled and a mass storage device is inserted either before or after a session starts, it’s redirected using client drive mapping.

When these conditions are true, the mass storage device is redirected using generic USB redirection:

  • Both generic USB redirection and the client drive mapping policies are enabled.
  • A device is configured for automatic redirection.
  • A mass storage device is inserted either before or after a session starts.

For more information, see

Feature Client drive mapping Generic USB redirection
Enabled by default Yes No
Read-only access configurable Yes No
Encrypted device access Yes, if encryption is unlocked before the device is accessed on the virtual session. Citrix Virtual Desktops only

Mixed DPIs with multi-monitors

Citrix Virtual Apps and Desktops environments do not support the use of different DPIs between monitors. You can verify the DPI (% scaling) using Windows Control Panel > Display options. If using a Windows 8.1 or Windows 10 client device, enabling the Let me choose one scaling level for all my displays option in the Windows Control Panel > Display options configures the monitors appropriately. For more information, see Knowledge Center article CTX201696.

Mapped client drives

As a security precaution, when a user logs on to Citrix Virtual Apps and Desktops, by default, the server maps client drives without user run permission. To enable users to run executable files residing on mapped client drives, override this default by editing the registry on the server.


Editing the registry incorrectly can cause serious problems that might require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

To allow access, edit the following registry key (create CDMSettings if it doesn’t exist):


Name: ExecuteFromMappedDrive


Value: 1 to allow permission and 0 to deny permission on mapped drives

The change takes effect for sessions connected after the registry edit.

Citrix Virtual Apps and Desktops 7 2006 is the first version to contain this registry location. Earlier versions of Citrix Virtual Apps and Desktops used a different registry location.