Sometimes a user may make a selection and the required applications cannot be executed. When an application is selected, the information required by that application and any applications it uses, must be accessible. For example, a function is dependent on an environment, thus the environment must be accessible. If all the associated information for an application cannot be accessed, invocation does not occur for the selected application. The following situations can cause an individual application to not be executed:

• The application is not verified.
• The application cannot be found.
• An application at the group or private level requires an application at a higher level that does not exist.
• The application is marked 'unavailable'.