Hard Drive recoverable?

[westsailor]

Sorry if this is not the appropriate forum to ask but I have no idea what to try next

I have a Win7 W500 with SSD boot drive and a 500Gb Hitachi drive (D:) in the UltraBay. I picked up a Win7 W530 with an SSD and added a 1Tb HD (D:) in the UltraBay.

So I'm transferring the data from the W500 HD to the W530 HD via a USB interface for the W500 HD. It's all data so I'm just copying/pasting folders from one drive to the other.

At one point when I selected a folder to copy I accidentally pasted it to a different folder on the same 500Gb drive. I cancelled the operation and closed the 'transfer in progress' window.

I'm not sure what happened (maybe I closed the cancel operation window too fast?) but now the W500 500Gb drive is is completely hosed. The drive is not recognized in the W500 Ultrabay ("Insert disk in Drive D:")

If I use a SATA external USB interface it is not present when I click on 'computer'. If I first open Device Manager it eventually shows up under 'Disk Drives' and now it's present when I click on Computer.

If I open up Disk Management it's present but the partition is grey so I'm unable to do anything, create a partition. Occasionally when I plug the drive into USB I get a message 'Drive must be formatted before it can be used. Format now?'. When I click on yes it says the disk cannot be formatted.

I've tried a couple 'free trials' for Disk Recovery S/W (promising to restore drives with corrupted partitions, etc.) but none of the software even sees the drive.

Does anyone have any additional ideas how to salvage the drive, make it usable again usable (I've given up on recovering any data)? Or do I now have a 500Gb paperweight...