High CPU usage is not a new problem with Windows computers as it has long affected both Windows 10 and 7 users. We recently covered how to fix high CPU usage after KB4512941 update in Windows 10. And now users are complaining about a process called msmpeng.exe causing a high spike in CPU usage. The interesting thing about this process is that it is not a virus but a system process run by the local antivirus itself. To better understand the issue, let’s move on and finally learn how to disable the msmpeng.exe process which will reduce high CPU usage on Windows computers.
Disable Msmpeng.exe and Reduce High CPU Usage
Before I move on to the guide, let me explain this. Msmpeng.exe is not a virus. In fact, the native antivirus is an Anti-Malware Service Executable process run by Windows Defender (now called Windows Security). Many users fixed the issue to a database file named mpenginedb.db. It is used by Windows Defender to store hashes. Due to some incorrect identifiers, Windows Security continues to scan all the data on the disk and rearranges them in the database file. As a result, CPU usage rises from 50% to 100%. To fix this problem we will need to delete the mpenginedb.db file.
Delete Mpengine.db File
1. Since Mpengine.db is a system file related to antivirus, we cannot delete it normally. We will need to temporarily disable the antivirus and then we can just delete the file. Open Windows Security and go to “Virus & threat protection”. Here, click on the “Manage Settings” option.
2. After that, disable all toggles below this section.
3. Now, Hold down the “Shift” button and restart your computer. It will boot into the Advanced Recovery Window.
4. Here, select Troubleshoot -> Advanced Options -> Startup Settings -> Restart. After that, press the “4” number key to boot into Safe Mode.
5. Once in Safe Mode, search for “registry” in the Windows Search box. Later on, Click “Run as administrator” in the right pane.
6. Copy the address below and Paste it in the registry address bar and press enter. You will be instantly redirected to the Windows Defender folder.
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender
7. Right click on “Windows Defender” and New -> DWORD (32-bit) value. Name the file “DisableAntiSpyware” and click the “OK” button.
8. Now double click on the file and change value to 1. After that, click the “OK” button and restart your computer.
9. This time, Search for “powershell” and open it as Administrator.
10. Then copy the following command and Paste into your PowerShell window. After that, press enter. This will delete the mpengine.db file from your computer.
Remove-Item 'C:\ProgramData\Microsoft\Windows Defender\Scans\mpenginedb.db'
11. Now open the Registry again and delete the “DisableAntiSpyware” file. After that restart your computer and Windows Security will start working again. And this time, you won’t see Msmpeng.exe causing any CPU spikes. If you are still facing the same issue, reinstall Windows or use a third-party antivirus, preferably Malwarebytes (FreePro version $47.30/year).
Disable Msmpeng.exe on Your Windows PC
This is how you can delete mpengine.db to reduce high CPU usage. As I said earlier, the problem is with Windows Defender, which is scanning the entire disk due to a false positive result. Although the process is a bit complicated, you can definitely do it if you follow the guide step by step. Anyway, that’s it for us. If you found the article helpful, let us know in the comment section below. Also, if the problem persists, try reinstalling Windows 10 from scratch.
