Microsoft Defender Antivirus is automatically disabled if a third-party antivirus app is installed on your computer. Microsoft Defender Not Working Due to 3 rd Party AntivirusĬheck if you have a third-party antivirus installed on your computer that prevents Microsoft Defender from working. Check That the Microsoft Defender in Enabled in Group Policy.Enable Microsoft Defender Using Registry on Windows 10.Enable Microsoft Defender Antivirus Services.Microsoft Defender Not Working Due to 3 rd Party Antivirus.
