WD My PASSPORT not working on any of my 3 computers

I have a WD My Passport on my desktop. It’s elatively new, have had it since January 2017 and this weekend, it doesn’t work at all.
I’ve tried hooking it up to two laptops and it is not recognized on these, either.
How does one know if it’s the actual external drive or the cable?
I would think that this external drive, barely 5 months old, wouldn’t be going kaput on me.
I did not purchase a special warranty at Office Depot where I purchased the hard drive, but I would think a 5 month old hard drive would still be under warranty.
Thanks for any insights.

I’ve found in my experience that very often the cable is the culprit in a case like this - however the only way to know for sure is to try another cable.

Is the drive seen in Disk Management?