Enter Windows Defender in the Search frame and press Enter. Press Windows + Q key combination to open the Search bar of Charm. Once you have removed these applications, Windows Defender will automatically open again. When you buy a new computer, or a new laptop, usually these computers, this laptop will install security software like Norton, McAfee, but these are just trial versions.Īfter you install applications such as Flash or Java, the program will notify you to remove programs, security software for free. Normally, users may not be able to identify and should not install security software. So in this case if you want Windows Defender to work, you must uninstall the 3rd party software, applications, antivirus programs and reboot your system. In addition, Windows Firewall is the reason Windows Defender is not working.

Therefore, in order to avoid this situation, Windows Defender will automatically turn itself off when it detects that another security program is installed on your computer. However, one of the problems that users often encounter when installing multiple security software on the computer often cause conflicts with these software and even cause many problems such as crash, closing errors. Windows is designed to detect the presence of installed security software.

If it detects that 3rd party applications, software, and antivirus programs are installed on your computer, Windows Defender will turn itself off. Change the date and time settings on Windows How to fix errors cannot open Windows Defender on Windows

Turn on windows defender windows 7