Antimalware Service Executable (MsMpEng.exe) is a core process of Windows Security (formerly Windows Defender) that provides real-time protection against malware and other threats. This process runs continuously in the background, scans files for potential threats, and applies security updates. Antimalware Service Executable is essential for maintaining system security. However, it can sometimes cause high CPU or memory usage. Users report that the Antimalware Service Executable Is Consuming High CPU or Memory after the Windows 11 update, significantly affecting system performance. Real-Time Protection Conflicts with Other Software, or sometimes, Windows Security may end up scanning its own files, leading to increased CPU usage. Here is how to stop the antimalware service executable from having high CPU or Memory usage in Windows 11.
Quick Links
Is MsMpEng.exe a virus?
No, the Antimalware Service Executable process is not a virus if it’s located at C:\Program Files\Windows Defender or C:\ProgramData\Microsoft\Windows Defender\Platform. You can check it by going to Task Manager > Details tab > right-click on MsMpEng.exe > select Open file location. If it’s not in the mentioned directory or any trusted folder, you may want to run a scan with another antivirus to see if it’s malware.
High CPU Usage by Antimalware Service Executable
As discussed, High CPU or memory usage by the Antimalware Service Executable can occur due to several reasons:
- Real-Time Protection: Continuous scanning of files, applications, and processes can lead to high resource consumption.
- Full System Scans: Scheduled or manual full system scans can cause CPU and memory usage spikes.
- Conflicts with Other Software: Incompatibilities or conflicts with other software, including other security programs, can cause performance issues.
- Large Update Files: Downloading and applying large security updates can temporarily increase CPU and memory usage.
Additionally, the Antimalware Service Executable may scan its own folder (e.g., C:\Program Files\Windows Defender), which can cause unnecessary resource consumption.
Perform a Clean Boot
A clean boot starts your computer with a minimal set of drivers and services, helping identify whether a background process is causing the issue.
- Press Win + R, type msconfig, and press Enter.
- Go to the Services tab. Check “Hide all Microsoft services” then click “Disable all”.
- Now switch to the Startup tab. Click “Open Task Manager” and Disable all startup items.
Click apply and ok then restart your PC. If CPU usage drops after a clean boot, a third-party service or startup app is likely the cause.
Change Windows Security Schedule
Most of the time, you will notice High CPU or RAM usage by the Antimalware Service Executable while performing a complete system scan. Changing the scan schedule to a time when you’re not actively using your computer can help.
- Press Windows key + S and type Task Scheduler, then press Enter.
- Navigate to Task Scheduler Library > Microsoft > Windows > Windows Defender.
- Right-click on Windows Defender Scheduled Scan and select Properties.
- Go to the Triggers tab and click on New.
- Set a new schedule that suits your convenience and click OK.
Exclude Windows Security from Scanning Itself
Sometimes, Windows Security might scan its own files, causing high CPU usage. To prevent such situations, excluding Windows Security from Scanning Itself can help reduce CPU/RAM usage.
- Open Windows Security by pressing the Win key + S and typing Windows Security.
- Go to Virus & Threat Protection.
- Under Virus & Threat Protection settings, click on Manage Settings.
- Scroll down to Exclusions and click on Add or Remove Exclusions.
- Click on Add an Exclusion and select Folder.
- Navigate to C:\Program Files\Windows Defender and add it as an exclusion.
Disable MsMpEng.exe process
Again, disabling real-time protection can significantly reduce CPU usage; you may consider it as a temporary solution, but it leaves your system vulnerable to threats.
- Open Windows Security.
- Go to Virus & Threat Protection.
- Under Virus & Threat Protection settings, click on Manage settings.
- Toggle Real-time protection off.
You can also tweak the Windows registry to completely disable Windows Defender and resolve this. Do this only if you already have a third-party antivirus program installed, as disabling Windows Defender leaves your PC vulnerable to threats.
- Open Registry Editor and navigate HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\ Windows Defender.
- Right-click on the main editor panel and select New> DWORD parameter (32 bits).
- Name this registry key DisableAntiSpyware and set the value to “1.”
Note: If the DisableAntiSpyware key is already there, no need to create a new one, edit it and change its value to 1.
Update Windows Security and Windows 11
Also, ensure that Windows Security and Windows 11 are up to date. The latest Updates include performance improvements and bug fixes for such problems.
To Update Windows Security:
- Open Settings by pressing the Windows key + I.
- Go to Update & Security.
- Select Windows Security from the sidebar.
- Click on Virus & Threat Protection.
- Under Virus & threat protection updates, click on Check for updates.
To install the latest Windows updates:
- Open Settings.
- Go to Update & Security.
- Click on Windows Update.
- Click Check for updates and install any available updates.
Run a manual scan using Windows Defender to ensure no malware or threats are causing the issue. Again, corrupt system files can cause high CPU or RAM usage, so running SFC and DISM scans can help. Updating all device drivers can also help resolve performance issues related to the Antimalware Service Executable.
