External Hard drive disappears

[Ranger850]

I have an External Hard rive that keeps disappearing from my computer. I van un plug it, the plug it in and the computer will see it for about 3-4 minutes, then it disappears and the computer cant read it. It is a "WD" My Book Essential 1TB hard drive. I have another one, 500G, it is older and works just fine. Does anyone have any knowledge of where I should start? Cables seem to be fine. I switched them out, and the problem is with the "box" not the cables.
pic of cables.

https://www.google.com/aclk?sa=l&ai=DChcSEwi2g-mWpfzyAhUNvcgKHU20ATcYABAMGgJxdQ&sig=AOD64_0dgsMx7TIBwAd4IU8eUmGR6S1hkQ&adurl&ctype=5&ved=2ahUKEwiw3duWpfzyAhWYPt8KHcL0CzwQvhd6BAgBEFc

link to what I actually have.

 

[Angie]

what os you running? and can you go to properties and assign a drive letter to it?

 

[Ranger850]

Running on macOS High Sierra. I'm new to the apple world and may need things explained to me. I will try to assign a drive letter and get back soon. Thanks @Angie

 

[Ranger850]

Sorry Don't Know if it matters but the Ext. HD is 2TB

 

[Dirtman]

Is someone stealing it?

 

[Ranger850]

can you go to properties and assign a drive letter to it?

I can't find "properties"

 

[Ranger850]

Is someone stealing it?

no

 

[Angie]

i can't help you. I know nothing to do with MAC or apple. sorry. good luck with it.

 

[Ranger850]

well that went south quick

 

[fastpakr]

Are these externals based around 3.5" desktop hard drives (external power supply) or 2.5" drives that are powered directly from the USB cable?

 

[Ranger850]

Are these externals based around 3.5" desktop hard drives (external power supply) or 2.5" drives that are powered directly from the USB cable?

They have an external power supply

 

[fastpakr]

Have you tried swapping the power supplies between them?

 

[Ranger850]

Have you tried swapping the power supplies between them?

That seems to have worked, without causing the 500G HD to "disappear". I hope 1 of the 1,000 old power cords I have at home will work, because I have to use both EHDs simultaneously

 

[Ranger850]

Have you tried swapping the power supplies between them?

I spoke too soon. it's gone again. 500G still visible. It still has the LED lit, it's getting power and it even shows up on the side bar. If i do nothing, it stays there, when I use the computer, it disappears after a few minutes.

 

[Ranger850]

The thing is, with this computer, you get a warning if you don't "eject" the device before you unplug it from the USB port OR the power supply. I'm not getting that, just all of a sudden, it's not there