Refreshing you USB Host Contrllers can often solve this problem. Disconnect your USB devices before proceeding:

1. Right mouse click on your "My Computer" Icon:
2. Choose "Manage" from drop down list
3. Then double click on "Device Manager"
4. On the list of components click on the "+" sign to the left of "Universal Serial Bus Controllers."
5.Highlight the first one "Intel(R)...Host Controller" and right click on it.
6. Choose "Uninstall" from the drop down list.
7. You will get a warning that you are about to uninstall this device.
8. Hit Ok.
9. Repeat steps 5-8 for every USB Host controller. All Host Controllers and USB Root Hubs should now be gine from the Device Manager.
10. Restart Windows. Windows will automatically reinstall fresh drivers. Wait until all "Found New Hardware" wizards complete themselves.

Now, reconnect you USB devices to the same ports they were in originally. They should now work properly.