External HDD suddenly not seen my MAC

I have a 3Tb ext HDD connencted via USB to my iMac.  It has worked fine for the last year. Today-suddenly- my iMac will not see the drive under spotlight, disk utility or “about this mac”.  Nothing. Nowhere. NADA.  I do not have any WD apps on my machine.  Help!


Make sure you test the drive on a different computer and with a different cable.

Does the light of the drive comes up?

It’s the external drive a Passport or a My Book?