Why do my USB ports not work?

I have had problems with USB ports and you first need to remove all USB devices and for the ones that are having USB recognition issues try them one at a time to see if they are recongnized. If one isn't that device might be faulty which can make other USB Devices not operate properly. Check all USB devices one at a time until you have found all the USB Devices that do not work. Then re-connect all the working USB Devices and toss the Inoperative one's.