virtualbox.org

I have vbox 4.1.6 installed; added the Extension Pack - USB works fine on the host. But using VRDP not so much. I am using rdesktop-vrdp like so:
I have created a universal USB filter (and also some specific ones - doesn't matter which I use, same result)

...the USB devices I plug in are seen by my Windows guest on the host - but Windows can never finish installing drivers. They all end up with "This device cannot start. (Code 10)" in Device Manager.

The behavior is the same on a Windows Host and an Ubuntu host.

This happens in guests running Windows XP and Windows 7, 32- and 64-bit, with and without UAC.

On the client end, I have tried from GNOME, from KDE, from XFCE, and from nothing but blank X screen. Same result no matter what. I have also run rdesktop-vrdp as root, so it isn't a "you don't have permission to access the USB devices correctly" issue. The users running the vbox host and the client are both members of the 'vboxusers' group, so it isn't that either.

Any ideas?

After a few more tries I was able to get it work... sometimes. The problem seems to be that the Linux host grabs the USB device and doesn't let go of it all the way -- the VM at the other end of the VRDP connection can never get complete control of the device, so it "cannot start." So does anyone know how I can tell my Linux host to quit grabbing control of USB devices? I need it to register the device only as far as allowing rdesktop-vrdp detect that it was plugged in, and then stop.