Hi Top,
Sorry to hear that another external hard drive seems to have "bitten the dust"
I'll give you a link below to your topic back in June this year where you will find some good information:
https://forums.whatthetech.com/index.php?showtopic=131507#entry886227
In broad terms the fault is likely to arise, either in the caddy and its USB cable, or the hard drive that is inside it.(so trying a known good working cable may be a wise first step.)
I would be inclined to try your external hard drive in several different computers, using different operating systems just to see if a fault with your USB port or cable is a likely culprit….
If you can't get it to be recognised in any of the machines you try then its pointing toward a fault in the caddy or its cable and or PCB or the hard drive that is inside.
If you dismantle the caddy it should be easy to remove the hard drive, and then this can be tested using an inexpensive converter cable. ( Just 2 or 3 dollars USA) However if you have a boxful of these drives then using an inexpensive hard drive docking station may be an idea for you to consider.(25 dollars or so USA)
We use quite fancy ( and expensive!) docking stations in the workshop in order to access data from practically any type of drive likely to be found in most modern Personal Computers..
However…
I have had a look on a well known American auction site and this is the sort of thing that may be suitable:
https://www.ebay.com/itm/All-in-One-2-5-3-5-SATA-IDE-HDD-Docking-Station-Clone-Hard-Drive-Dock-USB-HUB/140993822158?hash=item20d3e2fdce
However please make sure before making any purchase that you have checked out the bona fides of the seller and the specification to ensure that both meet your requirements. You may prefer a more expensive item manufactured in the USA by a firm or company that has a good local reputation and who may provide you with an after sale service.
If you are unsure on any of this it might be wise to ask your local competent, friendly computer technician to guide you on the best options for you, taking into account all your particular circumstances.
Regards
paws