1. disconnect the power from the box
2. reconnect the power to the box
3. at the same time as you reconnect the power, press the front-panel standby button repeatedly
N.B. the amber light will stop flashing and appear 'steady' quickly after this
4. as soon as the amber light goes steady, press the following sequence of front-panel buttons in brisk succession:
Up, Down, Left, Right.
This invokes a BIOS level HDD re-format and has - as I say - always worked for me. You still lose your content I'm afraid but it's a bit less bother than taking it apart. "
Bob, December 2009