In the win7 interface, click "Start Menu"> "run"> enter the command "regedit" in the lower left corner. Then, go to the window and locate:
HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \ Class \ {36FC9E60-C465-11CF-8056-444553540000} (applicable to Windows 7 systems)
Or
HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Control/Class/(applicable to Windows XP)
You will see a lot of items included in "{}", and then let's look one by one to see if there is a "Universal Serial Bus Controller (Universal Serial Bus controllers) "If you click, find the" upperfilter "or" lowerfilter "item in the right window and delete it. As shown in the following figure:
After restarting the computer, right-click "computer" on the desktop and click "device management" to find "operation"-"scan and detect hardware changes ", let the system automatically reinstall the driver. As shown in the following figure:
So that the usb can be used normally.