HD (with data) appearing in management but not My Computer

[glarimore]

The computer:
Celeron G550
8 GB RAM
ASRock B75M-DGS
OCZ Vertex 4 128 GB SSD
Windows 7 Ultimate x64

My father and I removed two hard drives from an Iomega 2 x 500 GB (RAID 0 -- mirrored) external that he had. We then threw one of the hard drives into the above computer. The problem we're having is that although the drive appears in the BIOS and in Disk Management, it is does not appear under My Computer. In Disk Management, the drive does not have a drive letter assigned and the option to change/assign a drive letter is grayed out.

I would like to avoid formatting the drive because we would like to keep the data from it. In the past, I have recovered data from friend's laptops by simply hooking them up internally to my computer, so I thought that that these hard drives would have similar "plug-n-play" functionality.

Anyone have any advice for getting the drive to show up?

Thanks,

Gustav

 

[zdbc13]

In disk management you will have to initialize the disks before you can use them. This means create a partition, format it, and Windows will assign it a drive letter.

The data was stored on a raid array in the Iomega and will not be accessible from a direct connection to your pc.