I have a WD 2TB Hard Drive with around 1.2TB of images on it, at a guess over 100,000 images. Tonight I copied several hundred on to a DVD via my lap top and when I formatted another disc I went to the hard drive to copy some more images on to a DVD the hard drive was empty?
Did you accidentally format the external drive? If you are considering professional recovery don’t try anything. You can try recovery software as long as the drive shows in disk management. Recuva http://www.piriform.com/recuva Is free. EaseUS and other companies have try and buy software.