I had a problem where the USB Controller for VMWare did not load. It turns out the USB Root Hub had the wrong drivers. The fix is to go into Device Manager and go through each of the USB Root Hubs and update the drivers for all of them to a driver provided by Windows. Detailed instructions in the link below.
Link: http://ericwijaya.wordpress.com/2010/03/12/vmware-usb-cannot-connect-to-host-usb/