A difficult problem that can be solved
How to Fix High Memory/CPU Usage of Antimalware Service Executable on Windows 10
The msmpeng.exe process is a critical Windows system process on your PC. It is a component of Microsoft Defender Antivirus, which runs in the background and helps protect your PC from malware infections, spyware, and viruses. Although it is considered essential, msmpeng.exe may sometimes report high CPU usage in Task Manager.
If you are using an older PC, this can cause your PC to run slowly (or become unresponsive). There are a few reasons why msmpeng.exe can cause high CPU usage. We will explain the causes (and some possible solutions) below.
Msmpeng.exe, or Antimalware Service Executable, is a crucial component of Microsoft Defender Antivirus, the built-in anti-malware and antivirus system on Windows 10 and Windows 11 PCs.