Using external harddrive (WB5000EBC035-01) after a while ... not working

Hi there everybody,

I haven’t used my WD external harddrive (WB5000EBC035-01) for a while, and this week I wanted to connect it
to my computer again. I found out I lost my power adapter.

After some research I found out this device needs a 12v 2a adapter with a 5.5/2.5 plug.
I bought a universal adapter that can provide exactly this.

Now i like to connect the external harddrive, but nothing happens. No blue light, no spinning
sounds inside. Also nothing pops up in windows explorer or anywhere else on my computer.

To put it simple, nothing works. Does anyone know what I could do to make it work again?
Thanks in advance !

Are you sure it’s actually getting the proper power? How do you know that aftermarket supply is good? Is the polarity correct?