i know that people have mentioned something similar here before, but I didn't see a thread that helped my situation, so I'm adding a new one. I have a Powerbook G4 I have a WD tera hd they used to get a long fine and talk to each other just fine. Now, it won't work. I can't read any external hard drive on my laptop, but both mine and my friends smaller 250g WD HD were visible on his mac. I don't understand why they won't show on my computer. they don't show up on the disk utility either. I hope some one can help. Thanks!