Yamaha Recording Unit

I have an older Yamaha Recording Unit that writes data to an internal 2.5" IDE hard drive. I have filled the drive, and would like to dump the data onto another drive for backup. I recently bought a 2.5" IDE internal drive enclosure, which plugs in via USB. The issue (I think) appears to be in the formatting. When I plug in the drive, windows recognises the drive, make the "Da Ding" sound, installs software, and tells me the mass storage device is ready for use. The drive does not show up in my computer, and I cannot seem to get it to work. I have tried it in a PC with no success. Is anyone familiar with some software that will allow my computer to pull off the data from the HD, and allow me to store it on my computer, and further dump it into a much larger external HD? The recording Unit is the AW4416 by Yamaha, I have no idea how it formats the disk for use, and I'm not absolutely positive this is in fact the problem.

Any suggestions?