This question is an exact duplicate of:
So I finally got my sata hard drive to power Directly from the raspberry pi 3 USB ports. But now when I plug it in and it powers on once I get on to the raspberry pi 3 it does not recognize or even show that the hard drive is plugged in. So I'm wondering what I do in this situation. I'll type in sudo lsblk and also blkid in the terminal and it does not show anything, Even when I go up to the top right corner where the injectable devices or it's still does not show. So I'm wondering if you can help me figure out why it is powering straight from the raspberry pi 3 but not showing up or being reconized.