Antimalware Service Executable High Disk, memory and CPU usage after 2018-03 updates

Hi Louis,

Antimalware Service Executable is one of the background-running services in Windows Defender. Antimalware Service Executable is running to scan the malware and spyware when you access them. It will detect if there’s anything harmful on your PC Aside from that, it also takes a background scan of your system for any viruses or worms. Its scanning relies heavily on your computer’s CPU, that’s why you find it’s eating the CPU usage on your Windows 10. To get this sorted, I suggest to follow the steps below:

Method 1: Change Windows Defender’s schedule

The error is mainly due to its real-time protection feature. Kindly follow the steps to  change Windows Defender’s schedule to fix it.

1. On your keyboard, press the Windows logo key and R at the same time to invoke the Run box. Type taskschd.msc and press Enter.
2. Double-click on Task Scheduler Library > Microsoft > Windows.
3. Double-click Windows Defender in Windows. Then double-click Windows Defender Scheduled Scan.
4. Uncheck Run with highest privileges.
5. Uncheck all the items in the Conditions section. Then click OK.

Method 2: Add Antimalware Service Executable to Windows Defender exclusion list

1. On your keyboard, press the Windows logo key and I at the same time to open the Settings window.
2. Click Update & security.
3. Click Windows Defender. Then click Add an exclusion in Exclusions.
4. Click Exclude a .exe, .com or .scr process
5. Type MsMpEng.exe. Then click OK.

Restart your PC and see if the issue persists.

Feel free to post back should you have further concerns.