Win XP, sp3 Host, Nas4free guest. VB version 4.1.16 with matching extensions installed.
I've rebooted, changed the sequence of when I plug in my USB memory stick, etc., have yet to see any usb device show up. I'm assuming when you add a USB filter VB is supposed to be showing existing USB devices? Else what is the icon with the green + for? The help tip says it will add a filter for the 'selected' device - yet I've never seen any devices show up.
Going to the command line - "vboxmanager list usbhost" shows <none>. I've tried it with / without VBox running, with / without my VM running - always shows <none>.
I've made a pass through uninstalling any windows application that may want to grab the USB device but may have missed something. Even when windows has grabbed the device, shouldn't it be listed in the list usbhost output?
Also, I've tried with / without EHCI box checked.