Uninstall and reinstall. in the install area where you can select a custom install, do so. Specify that this is an all users install. if the application still won't work or gives errors, then you need to download this : FileMon
Run that as an admin while you are logged in as the user. then launch the program as the user. This will allow you to look for any permissions errors that are occuring. If you find permission errors correct them. The bigest problem that using users has is that the setup is never developed for proper application support and usage. This is something I'm very familiar with as the environment I support is done this way.