Is it a PC that you bought from a shop, or did a friend a friend/you build it? I'm assuming it's a desktop PC as opposed to a laptop?
At the moment it is looking like a driver issue, and we can establish quite quickly if it is or not. But to help further we need to know which operating system you are using, please? Windows XP, 7, or 8 or something else? :)
Firstly you need to insert your usb drive to back-ward panel with your computer. Actually you need to connect directly the usb drive with the mother-board. Some computer does not support front-panel usb port. And after that please check the driver of your system. If you have windows xp, or windows 7 or windows 8 then it is fine these operating system does not required any usb driver. But if you use older version of operating system like windows 95 then your usb driver is required.