Uninstall it if you want to use Defender. Kind of unnecessary to run two antivirus apps on the same machine, at the same time. The error code for the same is 577, but you may or may not witness it. Using a third-party antivirus app will turn off Microsoft Defender automatically. Check again in the Task Manager (Ctrl+Shift+Esc). You may have been searching for the wrong program, thinking it is not running. As noted earlier, Windows Defender was renamed and is now part of Windows Security. However, they contain important background information about the topic. I am assuming that you have already tried checking for updates and rebooted your computer once before coming here. Microsoft probably already knows everything you do on Windows. After all, antivirus apps have system-level access. It is better to let Microsoft snoop on you rather than some other company. We will help you troubleshoot and fix the issue in this guide. I suggest you stick with Microsoft Defender. It makes little sense to download/buy a third-party antivirus app when the default one is solid and does the job. Note that Windows Defender was renamed to Microsoft Defender in early 2019 and is now part of a larger security product called Windows Security. Windows Defender is not turning on for you. It is completely free and comes preinstalled on all Windows installations. Please share and like below, also comment below for any problem encountered.Windows Defender has come a long way over the years and is currently one of the best antivirus products. Hope with this you have learn How to Enable or Disable (Turn ON/OFF) Windows Defender Using the Registry Editor. (if the DisableAntiSpyware does not exist, right click on the Windows or on Windows Defender, Select New, DWORD (32 bit )Value, rename it to DisableAntiSpyware and then enter the value 0 to enable or turn on Windows Defender). Turn OFF or Disable Windows Defenderġ) Launch Run by pressing Win + R on your keyboard.Ĩ) On the right hand side of the screen, you will see DisableAntiSpyware, double click on it and enter 0 as the value. On the left hand side, you will see HKEY_LOCAL_MACHINE, click on it to expand it.ħ) Expand Policies and scroll down to Microsoft, then select Windows Defender.Ĩ) On the right hand side of the screen, you will see DisableAntiSpyware, double click on it and enter 0 as the value. 2) Type in regedit on the run window and click on okģ) Click Yes on the UAC prompt to continue.ĥ) Navigate to: HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender.