
(FIX: Windows Defender has been turned off and isn't monitoring your computer).

If you don’t like the manufacturer's antivirus, then you can uninstall it from your control panel and then you can enable and use Windows Defender to protect your computer. When you buy a Windows 8 computer today, Microsoft Windows Defender is already bundled inside the new operating system, but for the reason that some OEM manufacturers prefer to install trial versions of antivirus protection programs from other manufacturers like Norton, McAffee, etc.

The Windows Defender (previously known as Microsoft Security Essentials) offers more protection to your Windows system from viruses, Trojans, worms and other malicious programs that can harm your computer. In Windows 10, 8, 8.1 operating systems, Microsoft updated its security protection with the Windows Defender Antivirus program.
