So I have an older WD My Book 1TB Ext HD. (USB2.0, FireWire400, eSata connections) I used it when I had a PC. Last time I turned it on was about 4 or 5 years ago, then I switched to Apple. It worked fine then. I recently found it and believe there may be data I'd like to retrieve. I'm not sure how to do it. I don't have a windows computer. I tried plugging it into my MacBook Pro but nothing happened.(it turned on, but the Mac didn't recognize it.) So I can't tell if it's because it was formatted for a PC or if the drive is actually malfunctioning. What's the next best course of action to problem solve this?