Hi All, Well I may have just learnt a difficult lesson - don't dabble. I removed the hard drive from my Powerbook 2400 with the intention of installing a compact flash card via a CF to IDE adaptor. In the first instance I had the wrong adaptor so I reassembled the Powerbook with the original hard drive. Upon switching on all I get is a green light. I've tried Sydney Ho's suggestion: GREEN LIGHT (constantly lit) 1. Disconnect AC 2. Pull Lion battery 3. Reconnect AC 4. Reset Power Manager button by depressing it for at least 40 seconds. No luck. This is very sad. Any ideas? Rob :(