External hard disk

i was trying to transfer some files from my laptop to the pc, using my external hard disk. when i connected the disk to the pc, it would not detect the disk. i even tried using different ports. it did not work. then i tried connecting it back to the laptop. but the laptop also did not detect it. i tried it on other pc's but it's the same. wht do i do now? i need the data on the disk.

note: when the disk is connected to any pc/laptop the light appears, indicating it is connected.

plz help, its urgent.