Arduino Nano 3.0 usb issue

I got my Arduino nano v 3.0 today. On connecting with PC, it starts and blinks, but the PC does not recognize it. So i cannot communicate with nano. The device manager returns it as 'unknown device'. Driver update did not help. Some person commented to try connecting pin 26 to ground as described here Arduino Nano 3.0 USB not recognized - Installation & Troubleshooting - Arduino Forum and Arduino Nano 3.0: FTDI USB locks up on power up - Bugs & Suggestions - Arduino Forum

Please help...

Thanks