Help with my new external hard drive

I just got a western digital passport drive and when i plug it in it does not show on the desktop. when i go to the disk utility it shows up on the side column, but when i try to partition it, it tells me there is an input/output error. Does anyone know what this means and how to fix it?

 

this is the info it shows at the bottom. the weird thing is, it isn't a 2 TB hard drive, it's only 500gb. i hope this is the info you meant, when I right click the drive it doesn't give me any other info.

Disk Description : WD Media Total Capacity : 2 TB (2,199,023,255,552 Bytes)
Connection Bus : USB Write Status : Read/Write
Connection Type : External S.M.A.R.T. Status : Not Supported
USB Serial Number : 202020202020202020202020 Partition Map Scheme : Unformatted