If you plug a USB flash drive into your computer and nothing shows up, or you get a "USB device not recognized" error, you might feel the need to panic. This can be caused by several different things, but most of the time the solution is simple. As long as the flash drive is in good shape and works on other computers, this is probably a minor issue that you can fix in a few minutes.
Examine the outside of the flash drive for cracks. If possible, plug the flash drive into another computer. This ensures that the problem is with the computer and not the flash drive.
Unplug the flash drive and shut down the computer. Unplug the power source to the computer. Wait 30 seconds, then plug-in the power source and restart the computer. Once it has loaded, plug the flash drive in and see if the computer recognizes it.
Click the "Start" menu and select "Run" from the list. Type "Devmgmt.msc" into the text box and click the "OK" button.
Click your computer as the target of the scan in the Device Manager window. Press the "Action" menu and select "Scan for hardware changes." If this locates the flash drive, then you're finished.
Go back to the Device Manager window. Open the "Universal Serial Bus controllers."
Right-click the first USB root hub in the list and select "Properties." Click the "Power Management" tab. Un-check the "Allow the computer to turn off this device to save power" check box and click the "OK" button. Repeat this with each of the USB root hubs.
Select "Scan for hardware changes" in the "Action" menu. If successful, the computer will recognize the flash drive.