I was recently using my external HD when it stopped working across the course of a week. Initially it gave me an I/O error and it does that now too when I try to explore the drive. It will not show up on My Computer but will show that there is a USB with a Passport attached in the USB connections. Furthermore, I tried to explore the media but nothing is there at all. Can you help me please? My research from the last 2 years was there and I need it for the work I have in the future.
What you could do is remove the drive from the enclosure. Get yourself another external SATA hard drive case (very cheap) and install the old drive into the new case. If the SATA interface on the old enclosure is bad, your computer might be having problems accessing the drive. Also listen closely to the drive and if you hear a "clicking or knocking" noise, that is indicative of a bad hard drive.
I tried to link the external hard drive to a SIIG superspeed usb 3.0 to SATA 2.5" enclosure and it would not fit inside. This is after I took the USB external drive outside of its casing. There were no screws or anything else to disassemble the device.