the local cptr technician says that the media of my ext hard drive is not working,,,, so data can never be recovered

Question

my external hard drive is "WD 320 GB",,,, once i connect it,,, it,s light gets on but the device is not detectable once i go into "my computer",,,, i've showed it to the technician at rawalpindi ( Pakistan),,,, he says there is problem with its media and data can never be recovered from it,,, please help me out