USB Standards
Are USB 2.0 and USB 3.0 Compatible? What You Need to Know
The USB 3.0 device you've plugged into the USB 2.0 port doesn't work. Why? It's not an error on your part, nor is it a fault in the device you're plugging in; it's simple compatibility issues between these two types of ports, and to understand this, this is an article for you.