Client/Host is Windows 10 Enterprise, hosting multiple VMs on Hyper-V.  

USB Pass through using RemoteFX over RDP is functional to Windows 8.1 Ent edition.

However, when RDPing to Windows 7 SP1 Ent, the USB redirection fails. This is for USB camera and Scanner.  These both show in the advanced local resource settings in the RDP client under Other supported RemoteFX usb Devices.

Drivers have been installed for the Scanner on the Win 7 VM but the VM does not find them even though according to documentation they should not be needed.

What else can I try to resolve passing the Scanner through?

Thanks!