[Karashata]

Sounds like it's unable to detect the hard drive, where it has to load the firmware files from. This may mean that the drive has died and needs to be replaced. I would check and see if you can get a hold of a 1.8" drive with a ZIF style connector and swap out the drive that's inside the player with it, then connect it in UMS mode to the computer and see if the computer recognizes it and can access it. If so, you'll likely want to format the new drive inside it, then you'll have to install the system files to the device so it can work.

I'd like to take a moment to ask a couple questions: First, do these players get used a lot? And second, have these players been dropped or thrown around a lot (ie. in a backpack or bag of some sort) while in use? Both of those could potentially wear the drive out a lot faster than it would be under moderate use in a more stable environment.