FIXED: Antimalware Service Executable High CPU Usage (MsMpEng.exe)

If the Antimalware Service Executable (MsMpEng.exe) is showing high CPU usage in the task manager, follow these steps to fix the problem.

MsMpEng.exe, known as the Antimalware Service Executable is a Windows Defender processes. To be more specific, the MsMpEng.exe process is responsible for real-time protection. As such, the process always runs in the background to provide real-time protection from viruses or malware threats.

Under certain circumstances, the antimalware service executable can cause high CPU usage in Windows 10. Some of the reasons for MsMpEng.exe’s high CPU usage include but not limited to virus infections, over scanning, etc.

Fix Antimalware Service Executable High CPU Usage

When the Antimalware Service Executable’s CPU usage is higher than normal, follow the steps below to fix the problem.

Jump to:

  1. Check for virus infections
  2. Exclude Windows Defender
  3. Disable real-time protection
  4. Use third-party antivirus

1. Check for Any Infection on Your System

The first and foremost thing you should do is see if your system is infected with any virus, malware, or adware. When a system is infected, Windows Defender is actively trying to remove the infection from the system. This leads to high CPU usage.

These are the steps to scan Windows 10 with Windows Defender.

  1. Open the Start menu.
  2. Search for “Windows Security” and open it.
  3. Select “Virus and threat protection“.
    15-may-20_21-43-37
  4. Click the “Scan options” link on the right page.
    15-may-20_21-43-42
  5. Select the “Full scan” radio option.
  6. Click the “Scan now” button.
    15-may-20_21-43-47

As soon as you click the Scan Now button, Windows Defender starts the scanning process. Depending on your system, the full scan can take quite a bit of time to complete. So, sit back and wait until the scan finishes.

If Windows Defender found any threats, it will remove them automatically. 

After removing any malware or confirming that your system is not infected, proceed to the below solutions if the problem still exists.

2. Exclude Windows Defender Folder

Under certain situations, the real-time malware protection engine tries to scan itself for unusual behavior and causes Antimalware Service Executable to use a lot of system resources.

To stop Windows Defender from scanning itself over and over, you can exclude Windows Defender from the usual scan. Personally, this is the method that worked for me. So there is a good chance it will work for you too.

  1. Press “Windows Key” to open the Start menu.
  2. Search for “Windows Security” and open it.
  3. On the right page, click “Virus & threat protection“.15-may-20_21-43-37
  4. Click on the “Manage Settings” link under the “Virus & threat protection settings” section.
    15-may-20_21-12-31
  5. Scroll and click on the “Add or remove exclusions” link.
    Windows defender click add or remove exclusions
  6. Click on the “Add an exclusion” button.
  7. Select the “Folder” option.
    Windows defender select folder exclusion
  8. Go to “C:\ProgramData\Microsoft\” folder.
  9. Select the “Windows Defender” folder and click the “Select Folder” button.
    Windows defender select windows defender folder

As soon as you click on the Open button, the Windows Defender folder will be added to the exclusion list.

Windows defender folder added to exclusion list

Once added Windows Defender will not scan itself constantly. This should reduce the overall high CPU usage by MsMpEng.exe process or Antimalware Service Executable.

3. Turn Off Real-Time Protection

If the above method did not work then as a last-ditch effort try disabling the Windows Defender’s real-time protection. Since the Antimalware Service Executable’s high CPU usage is caused by real-time protection, disabling it will instantly solve the issue.

Note: I don’t recommend disabling real-time protection completely. Treat this method only as a temporary fix.

  1. Open the Start menu.
  2. Search for “Windows Security” and click on the result to open it.
  3. Select “Virus & threat protection“.
  4. Click “Manage settings” under “Virus & threat protection settings” on the right page.
  5. Switch “Off” the option under “Real-time protection”.
    Windows defender turn off real time protection
  6. Click “Yes” in the UAC prompt.

As soon as you do that, the real-time protection will be disabled. Since Windows no longer scans your system continues in the background, the Antimalware Service Executable CPU usage will be reduced.

Windows defender real time protection

Again, this is just a temporary fix. DO NOT disable real-time protection for extended periods of time.

4. Use Third-Party Antivirus Solution

If the above methods did not work for you and the Windows Defender’s CPU usage is so high that you cannot use your system, ditch Windows Defender for third-party antivirus applications like Avast or AVG and Malwarebytes Anti-malware.

Just download and install Avast or AVG and Windows Defender will disable itself. Since Windows Defender is no longer the active antivirus solution, the MsMpEng.exe high CPU usage will not be an issue. Moreover, you will also get a bit more security compared to Windows Defender.

In addition to regular antivirus software, I also recommend you install Malwarebytes for better protection from malware.

Windows defender avast antivirus

Related: how to properly uninstall third-party antivirus from Windows

I hope the above methods help fix Antimalware Service Executable high CPU usage in Windows 10. If you are stuck or need some help, comment below and I will try to help as much as possible.

Leave a Comment

Scroll to Top