Some files are not being removed during uninstall

I created an installer using IS for one of my software programs. It installs the program files into a folder under the ProgramFilesFolder and the database into a folder under the CommanAppDataFolder. Everything works fine. The software program creates a few writable files like .ini and puts them into the same folder as the database under CommonAppDataFolder.

When the program is uninstalled the database is deleted but the folder and the ini created are NOT removed.

How can I ensure that all the dregs and miscellany created by the program during use are removed during or after uninstall?

Thanks

Dan