Windows Defender is the default anti-malware solution that Microsoft integrates with Windows. Many people choose to not use Windows Defender and choose to use for example ESET, Bitdefender or any other anti-malware solution. However, for normal computer users Windows Defender should be more than enough. But what if Windows Defender fails to start? What can you do to start Windows Defender? In this article we are going to show you a couple of ways to check if all settings are set correctly and that you don’t perhaps miss some important services, registry entries or files on your system.

• Windows Defender Will Not Open
• Windows Defender Will Not Turn Off Windows 10

This article is split up into different steps. We suggest you follow it step by step till once step solves your issue. If you were instructed to use a specific step, then ignore the rest.

Step 1: Reboot your system

Iobit uninstaller 6.3 key. Oct 25, 2015  Windows Defender is the default antivirus solution of Windows 10 just like it has been on Windows 8. The program is enabled by default and will turn itself off if another antivirus solution is installed provided that it is recognized by the operating system.

It might sound stupid but many problems with Windows Defender simply comes from a service not running, for example it crashed. By rebooting your system, you will restart all services that are needed again. If you tried this before then please continue to the next step. If this solution did not work then please also continue to the next step.

Step 2: Make sure no other services are causing issues

There could also be a service running which is causing these problems with Windows Defender, to make sure that’s not the case we will boot your system clean. This means that we only boot Windows with the only absolutely necessary services and programs. To see how you boot your system clean please read: How to Boot Windows 10 Clean?

If a clean boot did not help, then please continue to the next step. If clean boot did help, then once again use the guide above and start enabling Services again one by one or in small groups till you find the service that is causing the issue.

Step 3: Remove 3th party anti-malware, anti-virus and anti-spyware software

If you have any 3th party anti-malware, anti-virus and anti-spyware software installed then please completely remove these programs from your system by using the uninstallers provided by the publisher. If you cannot find the uninstaller then please use the list below to find the uninstaller for the software you are using, or the steps you should take to remove these programs.

AVG
Avast
BitDefender
ESET Smart Security
Kaspersky Internet Security / PURE
McAfee
Norton Internet Security
WebRoot

If your software is not in the list above, then please use google to find the removal tool for your program. You could use this search perimeter for example. [PROGRAM NAME] removal tool.

Once your 3th party application has been removed, reboot your computer and try to use Windows Defender again. If the program still does not work, then continue to the next step.

Step 4: Are you perhaps infected with malware?

A common reason for Windows Defender for not working is cause of an already present malware infection on your system which is blocking Windows Defender from starting. It’s` important to scan your system as soon as possible to determine if you’re already infected and your files or personal information might have been compromised. There are different kind of tools that can do this. Please use the two listed below first and see if they help.

1. MalwareBytes Anti-Malware The free version will do the job just fine.

If after scanning and removing any infections with both programs or if the programs did not find any infection, you still cannot start Windows defender then please continue to the next step.

Step 5: Restart the Security Center Service

1. Press the Windows and R key at the same time. This will open a Run window.
2. In the Run dialog type regedit and then hit enter or Run
3. In Registry Editor navigate to HKEY_LOCAL_MACHINESoftwareMicrosoftWindows NTCurrentVersionImage File Execution Options. By unfolding each folder step by step.
4. Look for any entry to MSASCui.exe, MpCmdRun.exe or MsMpEng.exe. If you find these then right-click them and choose Delete

If you do not find any entries at step 4 then no worries, that’s normal then this step is completed for you and you should continue to the next step. If you did find entries and deleted them then close Registry Editor and reboot your system. Once your system is rebooted check and see if Windows Defender now works. If not then continue to the next step.

Step 6: System File Checker Scan

You might have damaged files on your system which are causing the problems your experiencing with Windows Defender. To make sure you do not have any damaged files or to attempt to fix them please run an SFC (System File Checker) scan.

1. Open Elevated Command Prompt by following one of two methods:
2. Press the Windows + X at the same time, then choose Command Prompt (admin)
3. Type the following command “sfc /scannow” and hit enter
4. Wait for the results to come back.

If System File Checker found damaged files and was able to fix them then try to use Windows Defender again after you rebooted your device. If Windows Defender still does not work or SFC did not find any problems, then continue to the next step.

Step 7: Is Windows Defender disabled through the Registry?

Perhaps Windows Defender is disabled though the registry or the key is simply missing. We should check this.

1. Press the Windows and R key at the same time. This will open a Run window.
2. In the Run dialog type regedit and then hit enter or Run
3. In Registry Editor navigate to HKEY_LOCAL_MACHINESOFTWAREPoliciesMicrosoftWindows Defender. By unfolding each folder step by step.
4. Check if there is a DWORD DisableAntiSpyware

If there is no DWORD DisableAntiSpyware then right-click an empty location and choose New -> DWORD, enter DisableAntiSpyware and click on Create. Then double-click DisableAntiSpyware and set the value to 0. If there is a DWORD DisableAntiSpyware then check if the value is set to 0 if not set the value to 0.

You’ve reached the end of this article. We hope that one step was able to solve your problem. If there was no step that helped you then no worries, we might still be able to help you personally on our forums. We want to thank you for reading this article and hope it helped.

Since the advent of Windows 10, a considerable number of users are confronting somehow issues with Windows Defender. In this article, you will read an elaborated guide to fix Windows Defender not Working in Windows 10 comprising almost every variety of extrication and minute tweaks.

How to Fix Windows Defender Not Working in Windows 10

1. Restart

At first, Restart your system. There are certain services that need to work perfectly for Windows Defender, but somehow they get stuck and hence hinder the anti-threat program from working. Restarting the machine reboots all the components or services that are required for the Defender to trigger on. After attempting a restart, Windows Defender not working nevertheless continues, see the next one.

2. Get Rid of the Third Party Anti-Threat Software

With the presence of third party anti-threat software, there always arises a conflict between the third party programs which results in nothing good. These conflicts slow down your machine, applications get crashed, frequent freezing and lot more issues take place.

So, Windows Defender deactivates itself after it discovers the presence of other security programs. In the same way, if the outside program includes Firewall in it, then Windows Firewall also refuses to work.

Hence, to make Windows Defender perform correctly, get rid of the third party anti-threat software and restart the machine. After the restart, try to operate Windows Defender.

3. Scan for Malware

Another significant source behind not working of Windows Defender is the presence of any malware on your computer. A proper and thorough scan are required to find out them. The most used tools are the MalwareBytes Anti-Malware and Microsoft Safety Scanner.

Download the tool from their respective pages and make it run to search the malware. If you find some, remove the infections and reboot the system. See Windows Defender and if starts performing no issues, but if it refuses to not working look at the next step.

4. System File Checker Scan

Accidently or suddenly some files might get damaged on your computer which leads to the disturbance of Windows Defender. In order to ensure that your machine does not hold any of the destructed files, run the System File Checker Scan / SFC and when you find some, get them fixed. See how it is done:

• Jointly press Windows and X keys and from the appeared bar pick up Command Prompt (Admin).

• Say Yes to UAC.
• In the newly visible window, proceed ahead by typing this command: sfc /scannow

• Hit Enter key to run the command.
• Wait until it exhibits you the results.

If the System File Checker discovers any damage stuff, it thoroughly fixes it. Now, reboot the system and then try to start Windows Defender. And if nothing is found, try out the next one.

5. Confirm Whether Windows Defender is Not Disabled Through A Registry Key

Because of any previous mishandling of the registry keys it might happen that Windows Defender was turned off or may be its related keys has gone missing. The best advice is to check that in case Windows Defender went off with the registry key or not –

• On the Cortana text area, write regedit and she will present you the same as a result. Click on it.

• Once the Registry Editor window arrives, travel this way – HKEY_LOCAL_MACHINE => SOFTWARE => Policies => Microsoft => Windows Defender
• Now on the right pane look for the DWORD DisableAntiSpyware.

• See if the Value of the DWORD is set to 0 or not. If not, make a double click on it and upon the new Edit box, set the number to 0 and save the changes.

• If the right pane doesn’t show up any DWORD, make one then. Do a right-click on the empty area in the opposite pane of Windows Defender and opt for New, DWORD.

Windows Defender Will Not Open

• Assign it a name DisableAntiSpyware and put its value as 0 only.

6. Set Date & Time Settings Accurately

Many Programs functions accordingly Date & Time on Windows. So anything wrong in it could trigger the mess up. Ensure whether you have put its values accurately.

7. Ensure to download the latest update

Windows Defender Will Not Turn Off Windows 10

Windows update is often proves to be a big factor when you confront Windows Defender Not Working in Windows 10. So continuously set to automatically update your System. Apart from this check when you encounter the issue.

8. Check for wrong Zone settings and update Proxy Server in Internet Explorer

Inaccurate Zone entry on Internet Explorer produces flaw when Windows Defender from functioning. The only and straightforward process to overcome this problem is resetting of the browser. Hence reset Internet Explorer.

But Proxy Server could not be updated. For this purpose you will have to go manually. Follow the underneath steps:

• Jointly press Winkey+X. Move off with the choice on the 8th position from lowermost which says Command prompt (Admin).
• Copy the underneath codes and paste

NETSH WINHTTP SET PROXY 1.1.1.1:8080 or NETSH WINHTTP SET PROXY MYPROXY.NET:8080

• Hit Enter.

With these many steps, we are connived to fix Windows Defender not working. Based on diverse machines, the causes tend to be different. One step might resolve your machine’s Windows Defender and the other one might work well for another’s system.