I agree with other respondents, in all likelihood this is a driver
issue. However in defence of Windows 7 - it does install drivers
for USB2 ports automatically. If on the other hand the offending port is USB3 (you can tell by looking at it - if it is Blue then it is USB3) you will need to install a 3rd party (manufacturers) driver to get it going. In the meantime just use your USB2 (black) port (assuming that you have one). Of course there is also a small possibility that your USB controller chip has been damaged. I have seen this on a desktop computer, and instead of trying to fix it (which isn't possible without a surface mount soldering unit, and some mad soldering skills!) I just installed a 3rd party PCI USB card. Unfortunately as you are using a laptop fixing a damaged USB port probably means returning the laptop to the manufacturer!