The switch on the side marked on/off is not a power on/off switch. It should be marked "Lock on/off". When it is on then all other keys are disabled e.g. the volumes keys have no effect and even the main power on/off switch does not work.
The manual is just wrong about this key (page 4 step 8) as it is in other places.
Hope this helps.
Kevin Collins (knw10@aol.com), July 2005