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I want to use a Western Digital Elements 2TB portable external hard drive (WDBU6Y0020BBK) to back up which is USB 3.0. I realize that I will need to reformat to use this external HD. I have a USB Type-C to USB-A adapter that I use to connect my other external drive (USB 3.1) to the Thunderbolt ports, can I also use this adapter to connect the WD as well? Thank you!!
USB 3.0 and USB 3.1 can use the same USB-A connector on the computer end using an Apple USB-A to USB-C dongle. The cable for your WD USB 3.0 drive its self has a different end on the drive side which I think is whats confusing you. USB 3.1 drives use the USB-C connector on the drive and on both ends of the cable. You likely have a USB-C to USB-A adapter cable that came with your USB 3.1 drive besides the USB-C cable. You can’t use this adapter cable here as it’s not designed to support the older drive in the reverse configuration. Here’s a good write up on the USB differences: The USB standard
