external hard drive won't read- oyen 500

Recently bought an Oyen 500 external hardrive off craigslist, and it shows up under the icon tab at the bottom left, but it will not show up under my computer. I have a compaq laptop with Windows 7.

So I right clicked my computer, manage, disk management, and it first read: DATA ERROR (CYCLIC REDUNDANCY CHECK). I then changed the partition style to GUID, It was selected on a different partition style but I forget the name. Should I have done this? After I had done this, I was able to view the hardrive space, and it is showing up with 465.64 gb space (it is advertised as 500 gb), but its left without a name. It says Unallocated.

Any help would be much appreciated.

 

That is normal.
Right click on drive in disc mgmt and click make active.