We recommended that you backup your database(s) on a regular basis, for example once a week. You should especially do a backup after adding many new books. The backup can be used if some unusual event occurs which causes your database to become corrupt and non-recoverable.
The built-in backup feature will automatically backup your database to a standard zip file.
You can use the auto-backup feature to automatically backup the database when you close the database/exit the program. You activate the auto-backup feature in the Options window (Tools / Options / Backup).
To backup a database, choose Backup Database from the File menu, and select the folder you want to save the backup file.
To restore a backup, choose Restore Backup from the File menu, navigate to the folder the backup file is located, select the backup file, then specify the folder you want to restore the backup to.
Since the backup file is a standard zip file, you can also open the backup file with WinZip (or a similar program), and unzip the database file to the desired folder.