How to Fix High CPU Usage by MsMpEng.exe

Windows 10 has recently faced high CPU usage after the KB4512941 update. And now, Windows 10’s Antimalware service is causing high CPU usage. Many users have complained that the Antimalware service (MsMpEng.exe) is continuously using high CPU in the background. Fortunately, you can easily fix high CPU usage by the MsMpEng.exe process.

Many users doubted MsMpEng.exe to be a virus. But interestingly, it is Windows 10’s Antimalware Service Executable (a system service) and not a virus. MsMpEng.exe service is controlled by Windows Security (former Windows Defender) itself. So, in order to reduce the high CPU usage by MsMpEng.exe, we need to disable it. The process is not very straightforward but you can do it.

NOTE: This issue seems to be fixed in recent Windows 10 update. But if you are still facing the issue, you can follow this tutorial.

Disable MsMpEng.exe and Fix the High CPU Usage Issue in Windows 10

Many users have identified the issue to be with the database file (mpenginedb.db) used by Windows Security. And because of some false positive entries in the database file, Windows Security keeps scanning the whole disk causing high CPU usage. So, in this tutorial, we will disable Antimalware Service Executable and delete mpenginedb.db file to fix the high CPU usage issue in Windows 10. Follow these steps.

Step 1: Open Windows Security

Mpenginedb.db is a system file that is related to the antivirus, so, it can not be deleted normally. We will need to disable Windows Security temporarily. After that, we will be able to delete the mpenginedb.db file. So, first of all, open Windows Security and select “Virus and threat protection” from the left pane. Now, click on the “Manage Settings” link under the Virus & threat protection settings.

Step 2: Disable Windows Security Temporarily

Here, turn off the toggles for all services one by one. It will disable Windows Security completely. Don’t worry it’s temporary, settings will be changed to normal later.

SEE ALSO: How to Disable Windows Security (former Windows Defender) in Windows 10?

Step 3: Start Windows 10 in Safe Mode

After disabling Windows Security, we need to start Windows 10 in Safe Mode in order to disable MsMpEng.exe and fix the high CPU usage issue.

So, first, go to Settings > Update & Security. Here, select Recovery from the left pane and click on Restart Now button under Advanced Startup.

Next, you will see Advanced Startup settings. Go to Troubleshoot > Advanced Options > Startup Settings > Restart. After restart, you will see Startup Settings, press the F4 or number 4 key to boot into Safe Mode.

SEE ALSO: How to Start Windows 10 in Safe Mode?

Step 4: Disable MsMpEng.exe via Registry Editor

Once you have booted successfully into the Safe Mode, open Registry Editor. Type regedit into RUN and press Enter. If you see UAC Prompt, click Yes.

Copy and paste the following address in the Registry Editor’s address bar and press Enter. Windows Defender folder will open in Registry Editor.

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender

Here, right-click on the blank space and go to New > DWORD (32-bit) value.

Name this new DWORD DisableAntiSpyware. After creating the DWORD, right-click on it and select Modify. Now set its Value data to “1”. We have successfully disabled MsMpEng.exe and we are almost there to fix the high CPU usage issue in Windows 10.

Close Registry Editor and restart your PC.

Step 5: Delete mpenginedb.db File to Fix High CPU Usage

It’s time to delete mpenginedb.db database file. We will use Windows PowerShell to delete this file. So, now search for “powershell” and click on Run as Administrator from the search results to open PowerShell as an Administrator.

After that, copy the command below and paste it into your PowerShell window. Following that, hit Enter. This will delete the mpengine.db file from your PC.

Remove-Item 'C:\ProgramData\Microsoft\Windows Defender\Scans\mpenginedb.db'

NOTE: If you get an error while deleting the mpenginedb.db file, you can try restarting your PC in Safe Mode. After booting into Safe Mode, you can run the above command again to delete the mpenginedb.db file.

Step 6: Revert the Changes

After deleting mpenginedb.db file to fix the high CPU usage issue by MsMpEng.exe (Antimalware Service Executable), we need to revert the changes we did in Registry Editor. Go to the same path in Registry Editor again and delete the “DisableAntiSpyware” DWORD.

After deleting the DWORD, close Registry Editor and restart your computer. After restarting the PC, Windows Security will start working again.

After restarting, you will not see high CPU usage by MsMpEng.exe (Antimalware Service Executable). If your issue is not fixed yet, you can try resetting your Windows 10 or reinstalling a fresh copy of Windows 10. You can also use a third-party antivirus like Quick Heal or Malwarebytes.

Disable MsMpEng.exe on Your Windows PC to Fix High CPU Usage

The above tutorial explained how you can delete mpenginedb.db file and fix high CPU usage by MsMpEng.exe (Windows’ Antimalware Service Executable). After we cleared the Windows Security (former Windows Defender) database, it won’t cause high CPU usage by scanning the whole disk.

We hope you liked this tutorial. In case you are still facing any issues, feel free to write them in the comment section down below.

SEE ALSO: Speed Up Your Windows 11 and Windows 10 in Easy Steps.