شرح تنصيب اداة minidwep-gtk على الباك تراك ، لاختراق شبكات wep

Failed to open a session for the virtual machine BackTrack.
The machine 'BackTrack' is already locked by a session (or being locked or unlocked).
Result Code: VBOX_E_INVALID_OBJECT_STATE (0x80BB0007)Component: MachineInterface: IMachine {480cf695-2d8d-4256-9c7c-cce4184fa048}