When this directive is yes, the default, at startup Setup will look in the registry to see if the same application is already installed, and if so, it will use the language of the previous installation as the default language selected in the list of available languages on the Select Language dialog.

Note that this directive does not change the language used by the Select Language dialog itself because it cannot assume that the current user understands the same languages as the previous user. See the [Languages] section help topic for details on which language the Select Language dialog uses by default.

Also note that Setup cannot re-use settings from a previous installation that had Uninstallable set to no, since the registry entries it looks for are not created when Uninstallable is no.

UsePreviousLanguage must be set to no when AppId includes constants.