By Achilles Hill | Last Updated
The article summarizes some methods to open and use Windows Defender on Windows 8/10 computer for your reference.
Video guide on how to open Windows Defender in Windows:
Type windows in the search box on taskbar and choose Windows Defender from the result.
Step 1: Enter Start Menu.
Step 2: Select All apps, open Windows System and tap Windows Defender.
Step 1: Open Settings.
Step 2: Choose Update & security.
Step 3: Select Windows Defender and click Use Windows Defender.
Step 1: Get into Control Panel.
Step 2: Input win in the top-right box and tap Windows Defender in the options.
Step 1: Access Disk C/Program Files/Windows Defender.
Step 2: Open MSASCui.
Press Windows+R to show the Run dialog, type C:\Program Files\Windows Defender\msascui.exe and hit OK.
Open Windows Defender. In the Home settings of Windows Defender, choose a scan option from Quick, Full and Custom on the right, and tap Scan now button.
Tips:
Quick scan checks the areas that malicious software, including viruses, spyware and other potentially unwanted malware, are most likely to infect.
Full scan checks all the files on the hard disks and all your running programs, and it can take more time depending on your system.
Custom scan checks only the files and locations that you select, as shown in the following picture.
Step 3: Suppose viruses or other malware are detected, remove them according to the prompts.
Step 1: Open Local Group Policy Editor.
Step 2: Locate and open the "Turn off Windows Defender" setting.
It is in Computer Configuration/Administrative Templates/Windows Components/Windows Defender.
Step 3: Choose Not Configured (or Disabled), and click OK.
Step 1: Access Control Panel, input action center in the top-right search box and tap Action Center to get into it.
Step 2: Tap the Turn on now button on the right of "Spyware and unwanted software protection (Important)".
Step 1: Type services in the Windows search bar, choose Settings and open Services.
Step 2: Find and double-click Windows Defender Service.
Step 3: As the Windows Defender Service Properties window turns up, in General settings, click the bar beside Startup type, choose Automatic from the drop-down list and tap OK to complete the setting.
Start Windows Defender. Enter Settings, choose Administrator on the left, uncheck the small box before Turn on Windows Defender on the right and click Save changes on the bottom.
Step 1: Open Group Policy Editor.
Step 2: Find and open Windows Defender folder which is located in Computer Configuration/Administrative Templates/Windows Components.
Step 3: Access the setting called Turn off Windows Defender in Windows Defender folder.
Step 4: Choose Enabled and tap OK to enable the setting.
Step 1: Press Windows key+R to open Run dialog, enter services.msc and click OK to enter Services.
Step 2: Right-click Windows Defender Service in the Services window, and select Properties in the context menu.
Step 3: As the Windows Defender Service Properties (Local Computer) dialog appears, in General settings, click the small down arrow and choose Disabled as the startup type. Then, tap OK to finish the setting.
Step 4: Restart your computer to make the setting effective.
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