My Book essential not showing up in my computer

I bought a My book essential 3TB. It was working fine not to long ago. I stopped using it for a while and now it does not show up in my computer. I have searched posts on how to fix the problem. I have tried the computer management window but when I try to initialize and or do anything for that matter it comes up with an error that reads as follows “The request  could not be performed because an I/O device error” what does that exactly mean and how can I fix it. Need some help please.  Thanks in advance

This particular error normally means a connection or power issue.

Try using the drive with a different USB cable and make sure the drive is connected to a wall outlet directly.