On the next screen, Switch ON Real-Time Protection. Scroll down on the next screen and click on Manage Settings Link located under “Virus & threat protection settings”. In the right-pane, click on Virus & threat protection. Go to Settings > Update & security > select Windows Security in the left-pane. Manually Enable Microsoft DefenderĪfter removing Third-part antivirus programs, you may have to manually enable Microsoft Defender Antivirus protection on your computer. Repeat the above steps to uninstall all versions & modules of Third-party antivirus programs installed on your computer. Go to Settings > Apps > In the right-pane, select the Antivirus Program that you want to remove and click on Uninstall. After which, you should be able to Enable Microsoft Defender protection. Hence, the need to remove all previously installed Antivirus programs from the computer. Remove Third-Party Antivirus Programsīy default, Microsoft Defender gets automatically disabled, when it detects the presence of any third-party Antivirus program being installed on the computer.

Tip: In stubborn cases, the only way to fix this problem is by using Reset This PC option (See Last Method below). In certain cases, the problem could also be due to Microsoft Defender being blocked or disabled by Malware/Viruses and other reasons. If you Can’t Switch ON Microsoft Defender, after uninstalling McAfee or another Antivirus program, the problem could be due to traces or previously installed Antivirus program still being active on the computer.

Turn on windows defender antivirus