Operation Steps:
Locate the system run component for the service to start Windows Defender this software:
By opening the Run window with the keyboard "Windows logo key +r" (pressed at the same time), enter "Services.msc" in the input box to eject all components that the system service relies on, as shown in the following illustration:
At this point, double-click the mouse (or the right mouse click, select Properties), as shown in the following figure, the Start button is gray, can not click, or click on the display after the operation, but the error still can not be resolved, then please press to continue the following steps (win8/8.1 in this item, can be clicked after the normal start of this service):
First of all, it is necessary to confirm that the computer is not caused by the poisoning of Windows Defender this software can not run, this step is effective, if it is caused by poisoning, the method may be ineffective.
On the Start button in the lower-left corner of the desktop, right-click and select command Prompt (Admin), be sure to select the With administrator, copy the "SC start windefend Enable" (Do not copy quotes) to the cmd window, and then press the "enter" key
Then return to find the System Widows defender this software, two-point startup, you will find that the service is normal.
If it is still not normal, you can run the third step, then the first and second step, the service to start.
Note: The above method is suitable for Win10 system.
