i have 2 external hard drives, both western digital but different models... anyway, couldn't pinpoint when it happened but i can't get windows to recognise em anymore 
when you power em up, all the lights come on, you hear em spin up etc, but windows makes no attempt to acknowledge either of their existence...
what could it be? what could i check to get em back up and running?

when you power em up, all the lights come on, you hear em spin up etc, but windows makes no attempt to acknowledge either of their existence...
what could it be? what could i check to get em back up and running?