The disk contains important data and video files .Its around 2 TBIf disk management doesn't detect it then its most likely failed. Is the drive blank or does it have data on it?
It is external drive i tried connect the hard disk in different System but still same problemTry connecting it to a different computer first. Is it an external drive or an internal drive? If external, you might be able to remove drive and hook up directly to pc.
I tried to connect in different portTry another port.