I agree with hang-the-9, try it on another computer. If it works there, you know the problem lies with your laptop, if it fails on another computer then it almost certainly is a failed USB stick.
If it is your laptop, check the device manager to see if there is any errors showing with your USB ports and make sure you try to use all of the available ports as well. I've found uninstalling and restarting (drivers should automatically reinstall on reboot) to work for minor USB port issues.