Msmpeng.exe is a part of Windows Defender. If you are using Windows 7 and above, you might have seen Msmpeng.exe having high CPU usage frequently. The high usage isn’t confined to the CPU, though. The Msmpeng.exe can also use a lot of RAM, and increase the Disk usage. Sometimes, up to 80-85%.
The Msmpeng.exe is a process for the Windows Defender. Previously known as Microsoft Security Essentials. It comes pre-installed on all the computers running Windows 7 and above. It is a freely available antivirus software for protection against viruses, spyware, and malware. Though, there are hundreds of antivirus software available for Windows, what makes the Windows Defender special is that it is lightweight and fast. Unlike most of the other antiviruses like AVG and Avast which are notorious for being bloated, Windows Defender is a minimal piece of software.
Msmpeng.exe high CPU usage
Msmpeng.exe is a helper process for Windows Defender. This means that it allows the Windows Defender to scan for viruses and other unnecessary programs on Windows. Sometimes while doing its thing, this process can cause high resource usage in Windows. This problem is especially prevalent in Windows 10 where the Defender comes pre-installed.
Disable Sample Submission
On detecting a virus or malware on your PC, the Windows defender tries to send it to Microsoft for them to analyze it. This is to make Defender more secure and improved. This can, however, cause high network and disk usage on your PC. This is especially so for the people with older PCs and slow internet connections. If you have this problem, then the simple fix for that is to disable Sample submission inside Settings app > Update & Security > Windows Defender > Sample Submission.
Add an exclusion to the Defender itself
It’s been a known problem for quite some time; that Windows defender sometimes gets stuck scanning its files on Windows. This can cause high CPU usage on your PC. Adding its installation directory to the exclusion list can help fix this problem. Use the Settings app > Update & Security > Windows Defender > Exclusions > Add an exclusion. Click on Folders > Exclude a folder. On the selection box, type
C:\Program Files\Windows Defender and click on Exclude this folder button.
Disable other 3rd party antivirus software
Windows is smart in integrating 3rd party antivirus solutions by itself. This smartness means that after installing a 3rd party antivirus, Windows Defender automatically gets disabled. After installing something like, say AVG, if you got to Settings app > Update & Security > Windows Defender, you’ll see that Window has automatically disabled it.
This has some limitations, though. The problem is that Windows does this thing with the antiviruses which it recognizes. If you happen to use an antivirus which isn’t common, then sometimes, you’ll have two antiviruses running on your PC at the same time. Say for example, if you use a popular anti-theft service like Prey on your PC, the chances are that you will have high CPU usage due to Msmpeng.exe. Disabling either the Windows defender or the Prey anti-theft can fix the problem.