Setting Installation Conditions for an InstallShield Prerequisite

You need to specify installation conditions that determine whether an InstallShield prerequisite is already installed on the target machine. Failure to do so causes problems because the target system behaves as if the prerequisite was not properly installed. You can also create installation conditions that specify operating system, registry, or file requirements. The Conditions tab of the InstallShield Prerequisite Editor is where you set installation conditions.

If the InstallShield prerequisite should be installed on some—but not all—operating systems, you can create multiple operating system conditions for the prerequisite. If a target machine meets any one individual operating system condition, it meets the operating system requirements for that prerequisite.

If a condition evaluates as true at run time, that condition is met. The InstallShield prerequisite is installed on the target machine if the following are true:

The target machine meets any of the operating system conditions and all of the other conditions that are listed on the Conditions tab.

For feature prerequisites only (that is, an InstallShield prerequisite that is associated with one or more features in the main installation)—The feature that contains the feature prerequisite must be installed. Thus, if the feature has a condition that is not met on the target system, or if the end user chooses not to install the feature, the feature is not installed. As a result, none of its associated feature prerequisites are installed, unless the feature prerequisites are also associated with other features that are installed.