The driver is loaded when you connect the phone, all four of them.
With Win 7 and 8 - Connect the phone and uninstall the two items in the device manager related to the phone. Disconnect the phone and turn it all the way off. Connect it to the PC . The phone will turn on becuse it is charging. Drivers will load. This takes a while.
You should have the phone in portable devices in device manager and the phone with five folders in windows explorer.