Runtime App won’t run on Access PC

User createda runtime app for her department. All (who don’t have MS Access) can use it except one person who gets a missing .dll error when he tries to run it. This one person actually has MS Access 97 installed. We got around it by creating an icon for him that points to the application (MS Access 97) first and then to the database, but were wondering why he has to go in this ‘special’ way.