In Windows7, run Registry Editor, expand to Hkey_local_machinesystemcurrentcontrolsetservicesusbstor in turn, locate and double-click Start in the right window, and then in the pop-up window , modify its default value to "4".
Image above: Change the start value to 4 computer knowledge
After the modification, save the settings exit, the next restart can be effective.
After using this method, the USB device in the WINDOWS7 will be disabled, and if the user needs to enable the USB device, it must re-enter the above key value and modify the value back to "3".
The method described in this article is very "thorough" compared to the way to control permissions by elevating Windows7, but it is troublesome to modify the registry every time. Therefore, we do not recommend using this method.