A few suggestions to improve the file backup process:
(1) Provide an option to create an automatic backup every time the program exits.
(2) Allow the default backup file location (directory) to persist between sessions.
(3) As a default, append the date and time to each backup file, or append an incrementing file number, so that each new backup file does not overwrite the previous one. Ideally, allow the user to set a limit to how many old backup files are kept.