Sounds as if the drive has failed. The fact that you are failing to get any indication on two machines is also an indicator.
You could try opening the caddy up and checking connections and even using a dock for the bare drive to confirm this.
This thread is now locked and can not be replied to.
14 best budget laptops of 2015: best budget laptops reviews - best cheap laptops - best bargain…
1995-2015: How technology has changed the world in 20 years
Nokia rolls out spherical camera for virtual reality apps
From Antennagate to Yellowgate: The 10 worst Apple scandals (and why they were blown out of proport)…