Windows 7 Having a USB port automatically disabled upon devide disconnect

Three main ways of disabling USB ports - in the BIOS, in Device Manager and via the Registry. The first two cannot be managed automatically, the Registry possibly and could be achieved by use of a script (the key of interest is HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor ) but there would remain the problem of re-enabling as and when required.