The Msiexec.exe program is a component of Windows Installer as a client-side installer service. This program uses a dynamic link library, Msi.dll, to read the package files (.msi), apply transforms (.mst), and incorporate command-line options. The installer performs all installation-related tasks: copying files onto the hard disk, making registry modifications, creating shortcuts on the desktop, and displaying dialog boxes to query user installation preferences when necessary. When Windows Installer is installed on a computer, the file association capabilities of the operating system are modified to recognize the .msi file type. When a file with the .msi extension is double-clicked, the operating system associates the .msi file with Windows Installer and runs the Msiexec.exe application.