Download and install this driver: ggsetup-2.2.0.11.exe
Clean usb connector on the phone with needle,reinsert battery and try to connect.
Try few times but always reinsert battery before connecting.
Edit: Try with A2 uploader or Omnius identify button,if it will be detected you can flash it.Phone must be OFF before connecting,reinsert battery and don't forget to recharge it before flashing if phone will be detected.For Omnius you have to buy 1 day license but identify is free.