External hard drive not recognized? Why?

I changed my laptop some time ago. My external hard drive ran without problems on my old computer.

But I have had problems on the current computer.

Initially, I got the hard drive displayed after connecting it (with drive letter, volume, etc.) but could not access it because the computer first ran and then nothing opened (10 minutes).

Then I followed the tips available on the Internet and went through the Windows Device Manager settings.

Then the external hard drive was no longer recognized by my computer. (No display of an existing hard disk)

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What should I do

What can i try

What are the reasons why the hard drive is not called up or not recognized by the computer?

What tips did you follow from the internet?

Maybe because it is broken, or the case with the controller.
Try another PC.

I do not know whether you used your hard drive as a dump hard drive before or whether the operating system was running on it, but something can change in the data structure from Windows version to Windows version (7 → 8 → 10) and as a result something happened.

You may also have irreparable, bad sectors on your hard drive that are going crazy.

There can be a lot.