Win8.1 does not recognize the solution for USB connected devices

Xiaobian here to share with you is about Win8.1 unrecognized USB connection device solution, according to some users using Win8.1 system, when plugged in the USB mouse and keyboard, the system can not be recognized.
Fault phenomenon:
The computer prompt is not recognized, and the error message is found in the device manager: Unknown Device.

Cause Analysis:
This problem is usually caused by a device failure, USB interface, or system Plug and Play service being turned off.
Solution:
1, first click “Control Panel>---“Administrative Tools>---"Service”;
2, Open Plug and Play Services (Make The computer recognizes and adapts to hardware changes with little or no input. Terminating or disabling this service can cause system instability;
3. If the default is enabled, please disable and then turn it back on;

4, then open the device manager, uninstall the Unknown Device device, unplug the wireless device, restart the computer, plug in the wireless device, install the driver, you can.