The list contains 10 database locations sorted by date and time of the last access. New items are added to the list automatically, when a new database location is defined in the preferences.
The list's first item is reserved for the standard database location as created when you started DriveScan Plus for the first time.
If the option Let me choose the database whenever I start the program is not checked, DriveScan Plus uses the database location which was selected at this time.