Various problems can arise with USB redirection in Horizon Client.


USB redirection in Horizon Client fails to make local devices available on the remote desktop or application, or some devices do not appear to be available for redirection in Horizon Client.


USB redirection can fail to function correctly or as expected for the following reasons.

  • The device is a composite USB device and one of the devices it includes is blocked by default. For example, a dictation device that includes a mouse is blocked by default because mouse devices are blocked by default. To work around this problem, see Configuring Device Splitting Policy Settings for Composite USB Devices.
  • USB redirection is not supported on Windows Server 2008 RDS hosts that deploy published desktops and applications.
  • The device does not work well with USB redirection, or it is not supported with published desktops and applications. For more information, see Limitations Regarding USB Device Types.
  • Webcams are not supported for redirection.
  • The redirection of USB audio devices depends on the state of the network and is not reliable. Some devices require a high data throughput even when they are idle.
  • USB redirection is not supported for boot devices. If you run Horizon Client on a Windows system that boots from a USB device, and you redirect this device to the remote desktop, the local operating system might become unresponsive or unusable.
  • By default, Horizon Client for Windows does not allow you to select keyboard, mouse, smart card and audio-out devices for redirection. See
  • RDP does not support the redirection of USB HIDs for the console session, or of smart card readers. See
  • Windows Mobile Device Center can prevent the redirection of USB devices for RDP sessions.
  • For some USB HIDs, you must configure the virtual machine to update the position of the mouse pointer.
  • Some audio devices might require changes to policy settings or to registry settings.
  • Network latency can cause slow device interaction or cause applications to appear frozen because they are designed to interact with local devices. Very large USB disk drives might take several minutes to appear in Windows Explorer.
  • USB flash cards formatted with the FAT32 file system are slow to load. See
  • A process or service on the local system opened the device before you connected to the remote desktop or application.
  • A redirected USB device stops working if you reconnect a desktop or application session even if the desktop or application shows that the device is available.
  • USB redirection is disabled in Horizon Administrator.
  • Missing or disabled USB redirection drivers on the guest.


  • If available, use VMware Blast or PCoIP instead of RDP as the protocol.
  • If a redirected device remains unavailable or stops working after a temporary disconnection, remove the device, plug it in again, and retry the redirection.
  • In Horizon Administrator, go to Policies > Global Policies, and verify that USB access is set to Allow under View Policies.
  • Examine the log on the guest for entries of class ws_vhub, and the log on the client for entries of class vmware-view-usbd.
    Entries with these classes are written to the logs if a user is not an administrator, or if the USB redirection drivers are not installed or are not working. For the location of these log files, see Using Log Files for Troubleshooting and to Determine USB Device IDs.
  • Open the Device Manager on the guest, expand Universal Serial Bus controllers, and reinstall the VMware View Virtual USB Host Controller and VMware View Virtual USB Hub drivers if these drivers are missing or re-enable them if they are disabled.