User Guide

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About Microsoft Windows Installer
About Microsoft Windows Installer
To create a streamlined process for installing and managing applications, Microsoft
developed the Windows Installer service. It consists of a set of guidelines, an Application
Programming Interface, and a runtime service to help make application installation and
ongoing management part of the basic Windows system services. The Windows Installer
service is not an installation-authoring tool, but rather an installation engine and rule set
for installation packages. The Windows Installer engine resides on the destination
computer, reads the installation database (.MSI), and performs the installation and any
subsequent management, such as self-repair.
Instead of an installation executable (such as setup.exe), your installation is in the form
of a database file (.MSI), which contains instructions and can also enclose installation
files. Because this database uses highly structured, uniform data tables, there is 100%
accountability of where each file is installed and a thorough log of which files belong to
which applications. Because of this, individual files can readily be restored to repair
damaged applications.
Each table is dedicated to a particular type of installation information such as Class,
Components, Features, Files, Execution Sequence, and Registry. Certain logic is built in
to the Windows Installer engine, such as when to prompt for a reboot, disk space
checking, and file version replacement rules. When an .MSI is opened, msiexec.exe
reads the data stored in the database and builds an internal script to follow. It then
performs the actions in the script to complete the installation.
Microsoft Windows Installer comes with its own help system, which contains detailed
information on every aspect of Windows Installer. Access the Windows Installer SDK
Help by selecting Help menu > Windows Installer SDK Help. (In Visual Studio: Help
menu > Wise Help > Windows Installer Help.)
Frequently Asked Questions About Microsoft Windows Installer
How is Windows Installer different from Wise for Windows Installer?
Microsoft Windows Installer is a Microsoft technology for writing, managing, and
installing applications. The Microsoft Windows Installer service, which resides
permanently on the destination computer as part of the operating system, includes a
Windows Installer executable named msiexec.exe. The executable runs installation files,
called Windows Installer database files (.MSI files), that are written especially for
Windows Installer.
Wise for Windows Installer is an installation authoring application for creating Windows
Installer database files. When you build an installation in Wise for Windows Installer,
you populate tables within a Windows Installer database file. The Wise for Windows
Installer user interface exposes the functionality offered by Windows Installer.
How are files stored on the destination computer?
When an application is installed on the destination computer, Windows Installer stores
copies of .MSI files in a hidden directory named Installer, which is in the Windows or
Winnt directory. These copies are used if the end user attempts to remove, repair, or
reinstall the application from the Add/Remove Programs dialog. However, these .MSI
files do not necessarily store application files, so if the end user attempts a repair or
reinstall, Windows Installer might prompt the end user for the original installation source
(shared network directory or CD).
If you output an.MSI file compressed in an .EXE file, Wise for Windows Installer
uncompresses a copy of the .MSI into \Program Files\Common Files\Wise Installation