Hard disk is not displayed on laptop?

I bought an external hard drive for my laptop. But for three weeks, this is no longer displayed on my laptop that it is "connected" but it shines and rattles something in front of him. My ps4 recognizes them too i just have not tested them on another laptop yet. So why is that?

You can even look in the boot menu, if the hard disk is detected.
If not, it's either on the USB port or on the hard drive itself…

Ever looked in the Device Manager whether with the driver everything i.O. Is?

Look under Control Panel → Administrative Tools / Computer Management → Disk Management, if it is displayed there, if not what is with the USB port.