Gobain, this directly from Nokia "Do the following:
Disconnect the Nokia device from the USB cable and remove the phone's battery for 5 seconds. For phones with a non-removable battery (like N8-00 and E7-00), press the power button for 8 seconds until you feel it start buzzing and wait for the phone to start up again (and skip the next step).
Re-insert the battery then press and hold the phone power button for 1 second.
Re-connect the Nokia phone to the USB cable and wait for 10 seconds.
Try Nokia Suite or Nokia Software Updater again
If there is still no response, take your Nokia device to your nearest Nokia Care point. If the device is within its warranty period, Nokia will repair the device under the usual warranty terms and conditions."