Installation Program

The installation program plays the primary role in carrying out application installation. The program retrieves information from the user and the computer and installs the files and information needed to run the application successfully. Every installation program carries out these basic steps:

1. Determines the user's hardware and software configuration and available disk space.
2. Copies application executable and data files to the appropriate directories on the hard disk.
3. Sets up the execution environment for the application by modifying existing files and adding entries to the registry.

A Microsoft Installer Technology installation program (or a companion program) should also be prepared to update or remove an already installed application.

By using Microsoft installer technology, you can easily accomplish all of these steps. There are a variety of third-party tools available to make creating a Microsoft installer technology installation easy.

Windows also provides an Add/Remove Programs application in Control Panel that helps guide the user through starting the installation, update, or removal process. When the user chooses to install an application, Add/Remove Programs automatically checks the floppy and compact disc read-only memory (CD-ROM) drives for installation programs, searching for filenames such as SETUP.EXE and INSTALL.EXE. If a file is found and the user agrees to finish the installation, Add/Remove Programs starts the program and exits. After that, the started program is responsible for guiding the user through the rest of the installation process.