MY HD doesn't exist

My HD is a WDBACW0020HBK-00 My Book Essential. I am hooked up to a laptop with Win 10. It has worked fine as of a couple of weeks ago. No so today. I hook the HD to my Toshiba Satilite and the computer “beeps” I cannot find the HD anyplace in “My Computer”. It doesnt exist.

Hello,

Are you able to check if the drive is showing under disk management?

Make sure that the power cable is connected to the wall outlet.

I have tried the HD on 3 different computers with different connecting cables and I get the same results. “BEEP” and then nothing. I ran the WD diagnostic program and I got:
Test Option: EXTENDED TEST
Model Number: WDC WD10EZEX-60ZF5A0
Unit Serial Number: WD-[[DELETED - Privacy]]
Firmware Number: 80.00A80
Capacity: 1000.20 GB
SMART Status: PASS
Test Result: PASS
Test Time: 12:22:38, September 13, 2016

Under Disk Management, it shows “not initialized” and “unallocated”.