How to Install Windows Defenderby James H. Russell
Windows Defender comes installed by default on most modern Windows computers, but in some cases, the manufacturer of the PC may have deactivated the software in favor of another program. Depending on your version of Windows, the process for enabling the software is different.
Activating Windows Defender in Windows 8
Open the Windows Start screen and type "Windows Defender;" when you see the program appear in the search results, click it. The software will appear with red indicators all over the program dialog indicating it isn't active. Click the "Settings" tab, click "Real-Time Protection" in the list at left and then click "Turn On Real-Time Protection." Finally, click "Save Changes."
Activating Windows Defender in Windows 8.1
Open the Windows Start screen and type "Windows Defender." Click the program when you see it appear in the search results. If it appears as described in the previous section, follow those instructions. If, however, a small dialog telling you the software is not active and not monitoring your computer appears instead, uninstall whatever antivirus software you do have on your computer -- for example, McAfee -- and then Windows Defender should automatically enable itself. If it doesn't, follow the instructions in the previous section.
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