InstallScript MSI Installation Projects

The Windows Installer engine runs the standard Execute sequence of the .msi package. This is the sequence that typically modifies the target system.

The InstallScript engine serves as the custom user interface (UI) handler of the installation. It also executes the InstallScript code. The advantage of using the InstallScript engine for the UI is that it offers support for highly customized run-time dialogs.

In addition, InstallShield offers two different styles for the UI of InstallScript MSI installations:

Traditional style—This style lets you use the InstallScript engine as an external UI handler for your InstallScript MSI installation. With this style, your installation must include a Setup.exe setup launcher. The setup launcher serves as a bootstrap application that initiates the InstallScript engine to display the UI and run the InstallScript code, and the Windows Installer to run the Execute sequence of the .msi package.

New style—This style lets you use the InstallScript engine as an embedded UI handler for your InstallScript MSI installation. For this style, InstallShield embeds the InstallScript engine within the .msi package. The Windows Installer calls the InstallScript engine to display the UI. The Windows Installer also runs the Execute sequence of the .msi package.

This option requires Windows Installer 4.5 on the target machine. This option also has some limitations that require careful planning if you decide to use this style.

Because this project type uses two different engines, it is more complex than pure InstallScript or Basic MSI installation projects. It is recommended only for advanced users.

Traditional-style InstallScript MSI installations are less desirable to systems administrators than Basic MSI installations or new-style InstallScript MSI installations. That is because traditional-style InstallScript MSI installations require the use of Setup.exe, rather than being self-contained in an .msi package, and they may not be fully customizable prior to deployment. If your software will be customized by corporate systems administrators prior to deployment, create a Basic MSI project. As an alternative, you could consider using the new-style InstallScript MSI installations, but your must ensure that any system changes that need to be made are done with custom actions in the Installation Execute sequence. To ensure that sufficient privileges are available, custom actions should have an in-script execution setting of deferred in system context.

Additional Features for InstallScript MSI Projects

InstallScript MSI projects provide a few additional features that are not available in Basic MSI projects:

Additional InstallScript MSI Project Features
Feature	Description
Setup Types view	This view enables you to easily create different predefined installation configurations for your application, such as Typical or Compact. This view also enables you to select the defaults for the Custom setup type.
Billboard Support	Run-time billboard support is available for InstallScript MSI installations, but not Basic MSI installations. Billboards enable you to show bitmaps while files are being transferred to an end user’s machine. You can use these bitmaps to entertain or educate end users.