I spent over an hour of my time trying and finally found that the power cord was not powering the hard drive. At first I was completely confident and installed 4 hard drives, connected all cables and closed the case. After switching on, my computer only recognizes hard drives with old cables. Knowing my old data and power cable was fine, I found through trial and error that the power cable I bought was not providing any power at all. What a waste of time, not worth going to the post office and returning it for the seller to sell to someone else. The nonsense can go.