In ActionScript, as in any language, syntax is the way elements are put together to create meaning. If you use incorrect ActionScript syntax, your scripts will not work.
ActionScript export version incompatibilities are yellow in the Script pane. For example, if the Flash Player export version is set to Flash 5, ActionScript that is supported only by Flash Player 6 is yellow. For information on setting the Flash Player export version, see .
For a complete list of error messages, see Error Messages.