I've downloaded the latest virtualbox 4.3 for ubuntu 13.04. And I've downloaded the latest version of the extension pack for this version, intended to enable the use of usb on a guest operating system. My guest OS is Windows XP. When I go to settings to install/pickup a usb device before opening XP, virtual box doesn't pickup any usb device, doesn't matter which port I use. What can I do further? Before version 4.3, I had 4.2. I completely removed it and started over. Then I downloaded the latest version 4.3 and the extension pack in the hope that it would resolve my previous usb issue, but with no success. Please assist.