1. The first thing to try is to restart your computer.

2. If not a reboot should update the configuration installed on the computer equipment in the "device Manager". To do this, click on the icon "My computer" to open the menu and choose "Manage". Next, look for the tab "Action", "scan for hardware changes".

3.Disable the USB controller. Go to "device Manager" and delete all USB controllers, restart the computer. Don't worry, they will appear after restarting the computer.

4. Perhaps you have a damaged USB port. You need to check its condition. It needs to be like the rest, look carefully can you see any differences? Remember, whether got to port something to an outsider?

5. Another option of the USB failure is that the port is simply not connected to the motherboard. Maybe you took apart the computer and forget to plug in the connectors to the motherboard back?