Virtualbox error (in ubuntu) - implementation of the USB 2.0 controller not found!
i'm trying to add usb 2.0, but when click run in virtualbox, i get an error like this :
Failed to open a session for the virtual machine win7_test.
Implementation of the USB 2.0 controller not found!
Because the USB 2.0 controller state is part of the saved VM state, the VM cannot be started. To fix this problem, either install the 'Oracle VM VirtualBox Extension Pack' or disable USB 2.0 support in the VM settings.
in this video will help you how to fix that error.
enjoy.