USB devices on wyse T50

I am completely new to thin clients and wyse. I am trying to install thin clients for a community center and a small library. People need to use scanners and USB keys.

I use RDP with Windows Server 2008R2.

I can't get to make the USB devices work. The thin-client side seems to work. The devices are detected and enabled. But it doesn't go through to the windows RDP. I installed USB virtualizer, but it doesn't change anything. I tried to install TCX usb virtualization on the windows server, but it crashes during the installation. I have no idea how these work.