Since you are looking to format it we are not looking to save data here. Open a command prompt, run the "diskpart" command. Run "list disk" you will see your drives. Note which one is the drive you want to format. Run "select disk X" where X is that drive number. Run "clean" command, that will wipe all partitions off the drive. Go into Disk Manager and create a partition on that empty drive, format it. If you can't, your disk could be bad.