InstallShield 11
The InstallScript project type offers several options for the behavior of your installation when a target machine already has your product installed and the end user reruns the installation.
The Multi-Instance option lets your end users rerun an installation multiple times as a first-time installation rather than as a maintenance installation. By default, this option lets end users install the product to a different location each time that they run the installation. Each time that they run the installation as a first-time installation, the components that they select (whether directly or by selecting a setup type) are installed.
| Maintenance Experience | When Maintenance UI Is Displayed | Number of Entries Created in Add or Remove Programs |
|---|---|---|
| Standard | Whenever the installation is rerun | One |
| Multi-Instance | Only when the installation is rerun from the Add or Remove Programs | Multiple—a separate entry for each installation |
| No uninstall or maintenance | Never | None |
You can select these options from the Maintenance Experience property in the Project Properties view.
If there are multiple instances of your application on a machine, when a non-silent update installation for your application runs on that machine, it displays the Qualifying Product(s) Detected dialog. This dialog allows the end user to select the instance to which the update should be applied. If the update installation is silent, the update is applied to the first instance that is found, and the Qualifying Product(s) Detected dialog is not displayed.
The Maintenance Experience property works in conjunction with two other properties:
In addition, if the Maintenance Experience property is set to No uninstall or maintenance, you cannot set the Update Mode Supported property or the Enable Update Service property to Yes.