Have you tried connecting this drive to another computer to see if you get the same message? Before formatting connect the drive to another computer and if the computer recognizes the drive then make copies of your important files. If it is not recognized by another computer then try the simple things first such as a different USB cable and double check the power connection. If the drive is in a case, and not still under warranty, you could try removing the drive from the case and installing it as a second drive in your computer. If you are using a laptop and/or you don't have room for a second drive you could try a SATA to USB cable to connect the drive (this would either eliminate or confirm the case as the problem) or try a different drive enclosure or drive docking station.