In versions previous to 4D 2004.5, enabling the log file in Preferences (Log file checkbox) would automatically execute a backup. In 4D 2004.5 a warning dialog box informs you that a backup is needed in order to create a log file. Two buttons are available:

Cancel: The request to create a log file is saved but it is postponed until a backup is executed.

OK: A backup will execute and the log file is executed.