Connect the power plug into the b ack of the drive. It's okay if the drive powers on, then off, or if you see some lights come on for a brief second. Connect the USB or FireWire cable directly into your computer (do not use a USB or FireWire hub). If your drive has more than one port, only use one. WD my Passport External hard drive Set Up Guide Manual for Mac - Western Digital Use & Install. Pleasant 3d mac. Western Digital WD Elements 400 GB USB 2.0 Desktop External Hard. You’ll be able to use your WD Elements drive. But you will need an adaptor to plug the USB cable from your Elements drive into your Mac. These adaptor cables are easy to get from Amazon. And should your Mac be an older Mac with USB 2.0.