1tb My Passport lost format

I have a 1tb My Passport that up until last night had worked fine.  I plug it in and now instead of showing up with the assigned name it is listed as “Local Disk”.  The light is flashing and I can feel the drive spinning.  When I attempt to open the disk after a long process I get the message:

“Not Accessible. The Parameter is incorrect” along with a box telling me I need to format the drive to use it.  I’ve tried to open it on a PC running windows 8 and one Windows 7 and get the same message.  I have not yet tried to open it on a Mac.

Any ideas what might have happened?  Possible fixes?

I’m really just looking to get the data off the drive at this point.

Does the drive show in Disk Management?


It does…

It shows as online, 931.48gb RAW, Healthy (Primary Partition)

I assume this is a good sign?