msiexec.exe (msiexec stands for Windows Installer Component) is a Windows NT/2000/XP generic process used to install, fix, and remove programs included in Windows Installer packages (with the extension .msi).
The process msiexec is not in any way a virus, a worm, a Trojan horse, spyware, or adware.
msiexec is a system process which can be terminated.
