Windows Installer Custom Actions

Custom actions are actions entirely defined by the user. They can be executable files, dynamic linked libraries, Visual Basic scripts or JavaScript files. They can be scheduled at any time during the installation. There are four main stages in the execution sequence of the install package, where you can place custom actions: install, rollback, commit and uninstall.

• Custom actions in the install section are executed when the application is installed. They may create and save rollback information.
• Custom actions in the rollback section are executed when the application is installed, but something went wrong and the installation must be rolled back. The rollback information created and saved in the install stage may be used.
• Custom actions in the commit section are executed when the application is installed, after everything finished ok. Their usual role is to remove the rollback information saved in the install stage.
• Custom actions in the uninstall section are executed when the application is uninstalled from the target computer.

Additionally, they can be scheduled to be executed after any of the Standard Actions. These are grouped in three groups: before Initialization, before File Installation and before Finalization.

The custom action file can be a file installed with the application or attached to the package. In the first case, the file will be part of the application and, at install, it will be copied on the target machine. In the second case, the file is used only as a custom action and it is run from the installer package itself.

You can create and schedule Custom Actions in Advanced Installer in the Custom Actions page.