I have never had this problem before with my Mac, but now it's doing something funny. I do a lot of video work, so I have both a PC & Mac. I use a Fantom Drive (and external hard drive) to transfer all my files from school, different computers, ect. It has been working *perfectly* fine, until just recently. Now, my PC can find my external harddrive, but when I plug it into my Mac (Firewire 4 Pin), it can't find it! I don't really understand, since it has been working fine up until a few days ago. My firewire ports work (my iSight and iPod dock work fine), and my PC can detect my harddrive, but my Mac can't. Hmmm... strange indeed..