High CPU usage is often an issue with video games, antimalware software and more. Many of you are experiencing high CPU usage with Antimalware Service Executable or MsMpEng.exe and here we will discuss how you can fix it.
Antimalware Service Executable is basically associated with Windows Defender, which is responsible for your PC’s security in Windows OS.
Usually, we can drop the affinity of a specific process so that it’s limited to a set number of CPU cores or not using the CPU at all. However, this is a core Windows process and the affinity can’t be changed.
One reason behind the increased CPU usage by Windows Defender is because of the Full Scan. This feature basically scans every file present on your PC and checks them for compute virus.
This is the one that uses the most CPU and very little of it is left for users to utilize it for it other tasks. Hence, it causes delayed access and PC frequently hanging. You need to let the process complete and then continue with your task.
If the Antimalware Service Executable is still using 100% of your CPU or the CPU usage is very high, then the following fixes will help you.
Reprair Corrupted Files
The first fix for this issue is to repair the corrupted Windows Defender files. Check for updates and Windows OS should download updates for Windows Defender. This should repair the corrupted files and Windows Defender should be using the CPU within normal parameters.
Turn Off Windows Defender
One more fix for the high CPU Usage by anti-malware is to disable Windows Defender. One way of doing it by opening “Virus & Threat Protection” and click on “Manage settings” under “Virus & Threat Protection settings” and turn off “Real-Time Protection”.
This will prohibit Windows Defender from scanning files in real-time and will reduce CPU usage.
Reschedule Windows Defender
Another method to fix the high CPU usage by the antimalware is to reschedule Windows Defender. Click on the Start menu and type “Administrative Tools” and open it.
Double-click on “Task Scheduler” and browse the path “Library/Microsoft/Windows/Windows defender” from the left pane. Look for “Windows Defender Scheduled Scan”, click on it once and click properties. Go to the “Conditions” tab uncheck the options under Idle, Power, and Network and apply the changes.
Now again open properties and this time go to the “Triggers” tab. Click new > weekly or monthly (your choice) > choose a day and click OK.
After this, the Windows Defender will only scan at the scheduled time and only at that time you’ll see high CPU usage. Repeat the process for “Windows Defender Cache Maintenance”, “Windows Defender Cleanup” and “Windows Defender Verification”.
Delete Bad Updates
Open CMD by pressing “Windows + R”, type “CMD” and press “Shift + Ctrl + Enter” to give it administrative rights. Type the following command and press Enter.
“%PROGRAMFILES%\Windows Defender\MPCMDRUN.exe” -RemoveDefinitions -All
After that, type in the following command and press enter.
“%PROGRAMFILES%\Windows Defender\MPCMDRUN.exe” -SignatureUpdate
Wait for the process to complete and the CPU usage should return to normal.
Scan For Malware
There is a chance that MsMpEng.exe process has been infected by a malware that is using your CPU for its own purpose. Scan your system for malware with a good anti-malware software.
Add MsMpEng.exe To Exclusion List
Adding the MsMpEng.exe to the exclusion list will reduce the CPU usage significantly. Open “Virus & Threat Protection” and select “Manage Settings” under “Virus & Threat Protection settings”.
Click on “Add or remove exclusions” under Exclusions. Click on “Add an exclusion” > select “process” > paste MsMpEng.exe and click add. This will exclude the “MsMpEng.exe” process and the CPU usage should drop.
That is all for our fixes for increased CPU usage. You can also see our Fixes for Windows 10 Unspecified Error 0x80004005.