This process points to Microsoft's product called Windows Defender. This security product serves as a defense against spyware and unwanted software. Upgrades to the product made it less intensive when running locally on a computer. Windows Defender allows the user to run a quick scan or a full scan of the computer. Additionally the product provides the facility of running a custom scan within a specified repository. The process should never be closed off through the Task Manager; instead it can be simply removed by closing the application itself. As with any other malware/virus detector, the application needs to be updated regularly to utilize the latest of virus/spyware definitions. This can be done manually through the Update section of the product.
The main functions of the msmpeng.exe file include the ability to remove, quarantine, and prevent spyware infections. Apart from scanning for spyware, the msmpeng.exe file also searches for worms and trojans.
The framework of the msmpeng.exe file was based on the GIANT Antispyware, a product of GIANT Company Software, Inc. Apart from scanning, Windows Defender also includes various real-time Security agents used to check areas of Windows that can contain unsafe programs. ActiveX applications can also be removed by the msmpeng.exe file.