MsMpEng.exe Guide

Windows has a pre-installed anti-virus known as Windows defender. It protects the PC from harmful malware with the help of Antimalware service executable. This process can be seen as the MsMpEng.exe extension in the task manager’s details list.

It runs in the background to ensure that no viruses or hackers can attack your computer. MsMpEng.exe works by scanning all the new files and determining if there are any infected files. It removes or quarantines such corrupted files so that they won’t harm the PC. It also monitors the PC round the clock to kill all the Trojan infections.


However, there are many complaints about MsMpEng.exe using up too much CPU space. This could transform into a troubling issue if you ignore it. It might lead to low CPU processing and low memory space, which renders your PC extremely slow in the long run.

If you are facing such a situation, you have come to the right place. This article will explore the major causes of this high CPU usage and explain a few methods to resolve this issue. Without wasting any more time, let’s start with this article.


Why Is MsMpEng.exe Using So Much CPU?

Numerous things result in MsMpEng.exe using a high amount of space on the CPU. The Windows defender runs all day and provides real time protection to the PC. It also checks all the files on the PC at the scheduled times. Due to these constant scans, MsMpEng.exe puts a heavy strain on the CPU.Apart from this, the Windows defender might be scanning its own folder.

Low hardware resource is another reason causing high CPU usage.MsMpEng.exe eliminates the viruses. So, there might be adware or malware hidden somewhere in your PC causing this issue. Even corrupt system files, outdated versions of Windows defender, auto-scan, and certain software discords could result in high CPU usage.

Whatever the reason may be, there are few methods to tackle the problem. Of course, you can download a free or paid third-party anti-virus and disable Windows defender. But, it is advisable to try out the techniques mentioned before jumping to any conclusion.

Method 1: Prevent Windows Directory From Scanning

Step 1: Either go to the settings, click on Update & security, then on Windows security or search for ‘Windows Security’ in your taskbar and open the app.

Step 2: Click on Virus and threat protection’

Step 3: Find the manage settings option and click it

Step 4: Look for a section named Exclusions and select ‘Add exclusion’

Step 5: You’ll get an option for choosing folders. Browse through it and select this path – c:\Program Files\Windows Defender

This will put the app’s directory in the exclusion folder and Windows defender won’t scan itself.

Method 2: Limit CPU Usage

Step 1: Right click on the taskbar and select Task manager’. Or use ctrl + alt + delete shortcut and select ‘Task manager’ from there.

Step 2: In the task manager, go to the ‘Details’ section

Step 3: Scroll down and look for MsMpEng.exe. Then, right click and click ‘Set affinity’

Step 4: In case you receive a message saying ‘access denied’, follow these steps

  1. Right click on MsMpEng.exe and select ‘Properties’
  2. Go to the ‘Security’ tab and you’ll see the ‘Edit’ Click it.
  3. In the box below, give full control to the administrator. Now try setting affinity again.

Step 5: Once the affinity box is open, select the cores you want this service to use.

Doing so will reduce the power of the MsMpEng.exe process, thereby reducing the CPU usage by the process.

Method 3: Start Your Computer in Safe Mode

For Windows 10 –  

Step 1: Open Settings

Step 2: Go to Update and security’ and open the ‘Recovery’ tab

Step 3: Click the Restart Now’ button

Step 4: After your PC restarts, you’ll see a screen asking you to choose an option. There, select ‘Troubleshoot’,

Step 5: Then go to Advanced options’

Step 6: Click on Startup settings’, and finally select ‘Restart’.

Step 7: Press ‘F4’ on your keyboard and the PC will restart in safe mode.

For Windows 7 –

Step 1: Restart the PC

Step 2: Before you see the logo of the Windows, press ‘F8’

Step 3: The Windows advanced options menu will open. Choose ‘Safe Mode with networking’

Method 4: Remove Adware

MsMpEng.exe is one of the common issues of high CPU usage. Internet is a vast space and has tons of adware, malware, and other viruses. They might cause any level of harm to your PC’s working.These viruses may have hacked MsMpEng.exe. And they might be hampering the process of MsMpEng.exe.

It is not impossible to get rid of such adware from your computer. You have to get a reliable anti-virus or anti-adware and scan your PC. The scan doesn’t take much and quickly tells you the status of your PC. If there is any adware or malware, it will automatically remove it.

In this way, you can improve the working of the processes, reduce the load of the CPU, and protect your PC. However, always create a backup of your files as a precaution. One never knows when a strong malware corrupts your files.

Method 5: Reschedule Windows Defender

Step 1: In the search bar, type in task scheduler

Step 2: Open the app

Step 3: In the task scheduler library, find and click Windows defender’.

Step 4: In the box on the right side, look for Windows defender scheduled scan. Double click it.

Step 5: In the next tab, click on Conditions’. Now, see that the options – start this task only when the computer is free, start this task when the PC is on AC power, and start only when the following network connection is available, are disabled.

Step 6: Save the changes made.

Step 7: Further, go to the ‘Triggers’ section in the properties tab

Step 8: Select ‘New’

Step 9: Choose monthly and select the day for the scan. You can even choose weekly, if a month seems like a long time.

Step 10: Once you are done, head back and do the same for other tasks of the Windows defender.

This method is a bit lengthy, but it has a high chance of solving the High CPU usage issue. Since the defender won’t scan, the MsMpEng.exe process won’t start. Hence, the CPU will give a smooth performance. Though it might put a load on the CPU when it scans on the scheduled day, it would resolve within some time.

Method 6: Disable Windows Defender

With the help of Group Policy editor –

This is only for those having Pro or Enterprise Windows. If you don’t have that, use the next technique to disable the defender.

Step 1: Press the Windows key along with R.

Step 2: Enter and open gpedit.msc

Step 3: On the left side, find ‘Computer configuration’.

Step 4: Then, click on Administrative templates’

Step 5: Further, click on Windows components’.

Step 6: Finally, navigate to Windows defender antivirus’

Step 7: Double click on the option of Turn off Windows defender antivirus’

Step 8: In the new window that opens, select ‘Enabled’, hit Apply and OK.

By using registry editor –

Step 1: Open the run dialog box by pressing Windows key + R.

Step 2: Search for regedit.

Step 3: In the registry editor, go to the following path –

Step 4: After this, double click on the DisableAntiSpyware Dword. In case it isn’t there, right-click and create a new DWORD (32-bit) Value folder. Rename it to DisableAntiSpyware and open it.

Step 5: Change the value data and set it as 1. Then, save the changes.

This is a sure-shot way to kill MsMpEng.exe and lower the burden on the CPU. However, make sure you install another anti-virus software to protect your PC from threats.

Method 7: Disable Sample Suspension

Usually, Windows will send the errors, including corrupted extensions and files to Microsoft to look into them. This could be a reason behind the high CPU usage by MsMpEng.exe. So, try disabling it and check if it works.

Step 1: Open Updates and security’ in the settings menu

Step 2: Click on Windows security

Step 3: Further, choose Virus and Protection’

Step 4: Go to Manage settings’ below virus & threat protection settings

Step 5: Navigate to Automatic sample submission’ and slide the on button to off


It feels like a betrayal when the app that protects your PC ends up lagging it. Nonetheless, Windows defender is a great anti-virus program. Normally, it won’t give you any problems on routine days. However, if the CPU usage is high due because of it, the above steps must help you.

MsMpEng.exe isn’t malware. It has a crucial role in defending your PC from all sorts of cyber-attacks. You do not have to remove it but can restrain its working by following the methods. If nothing works, you should just disable the defender and install a new anti-virus.

Note: Never leave your PC without anti-virus software. You’ll get a lot of virus attacks within a few minutes of internet usage.