This solution applies to both jamilaht06 & Eppij.
Sounds like the firmware is corrupt or deleted.
Install and run the Philips Device Manager from the product CD.
Connect the player to the PC.
Wait for the PC to recognise the player then select the Repair/Restore option and follow the on-screen prompts.
This will format the player and reload the firmware.
NOTE: ALL TRACKS WILL BE DELETED FROM THE PLAYER
If the problem persists, it could be a faulty hard disk in the player. This is a standard Microdrive.
If this is the case, www.cheapestelectrical.co.uk
have a couple in stock. (Only 6GB). They are not on the site, so you will need to e-mail them.