The hard disks inside the recorder should be exchangable. If you still have warranty, bring the machine to your point of purchase, or repair shop, as directed by the shop you got it from.
As you are at it, consider asking to change to a bigger size HD, and pay a little for the prize difference?
If out of warranty, try changing the disk. These machines should be easy to open, as long as you do not have the electrical cord plugged in and do not touch capacitors that might hold remaining charge.
However, although the disks are mostly standard IDE disks, there might be a software specific to this brand of recorder on the old hard disk, so pls find out if there is downloadable boot images existing that you could transfer.
You might even have a corrupted boot image... and not a broken disk.
Here is a discussion thread with pros and cons about changing the disk:
http://forum.doom9.org/archive/index.php/t-128974.html