Some malware camouflage themselves as msiexec.exe, particularly if they are located in c:\windows or c:\windows\system32 folder. Thus check the msiexec.exe process on your pc whether it is pest.
Msiexec.exe is an executable process of Microsoft Installer. It is usually started when you are installing an application, and typically ends after installing the application. It has been known to remain after the application has installed, and can automatically launch at computer startup, where it uses large amounts of system resources. If you have already installed your application, you can stop its running process and disable it, which removes it from startup to prevent it from running.
Stop the Msiexec.exe running process.
To do this, open the Task Manager by pressing "Ctrl," "Alt," and "Delete" together.
Click the "Process" tab. Scroll down and click "Msiexec.exe." Click "End Process" to stop this running process. Close the Task Manager.
Click the Windows "Start" button and click "Run." Type
and press "Enter" to open the Services window.
Scroll through the Services window and double-click "Microsoft Installer." Select "Disabled" in the Startup-type window. Click "OK" to save the changes. Close the services window.