Airport Extreme HDD unreadable Windows Fat32

I have a WD My Book 500gb hard drive that I was using as a backup via the airport extreme. It was formatted as fat32 for compatiblity. I had been restoring some files back to my computer via wireless, but the HDD kept dissapearing after a few gigs and I'd have to hard cycle the drive to get it to appear on the network again. I decided to unplug the drive and plug it directly into my windows PC. When I did that, it did not show up in the file explorer and disk manager says the drive is all unallocated space. When I plug the drive back into the airport extreme, it cannot be seen on the network or by airdisk. I really need some files off this drive. I have tried some partition recovery software to no avail. What can I do to get my files back?

Thanks