Since you told nothing about the make and model of the drive, make and model of the PCs, and the operating system, that's all I can offer.
I have this external Hard Drive which holds about 300gb and recently i went and copied all these movies and series from my friends laptop..
then suddenly after waiting awhile their laptop froze and so we had to take out the battery then unplugged the hard drive out of the usb..After that my hard drive hasn't been recognised in my friends laptop or mine.
However the light still turns on and the disk inside is still moving ...what has happened and how can i fix this problem?

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