private BackupPeriod getBackupPeriod() {
		BackupPeriod backupPeriod = BackupPeriod.DISABLED; // Set backupPeriod to default: DISABLED.
		String backupPeriodString = Controller.getProperty(ApplicationProperties.BACKUP_PERIOD);
		boolean backupPeriodNull = false;
		
		if (backupPeriodString != null && !"".equals(backupPeriodString)) {
			backupPeriodString = backupPeriodString.toUpperCase();
			try {
				backupPeriod = BackupPeriod.valueOf(backupPeriodString);
			} catch (IllegalArgumentException ex) {
				backupPeriodNull = true;
			}
		} 
		if (backupPeriodNull) {	
			Controller.setProperty(ApplicationProperties.BACKUP_PERIOD, backupPeriod.toString());
			AlertMessages.backupPeriodIllegalArgumentException("BackupBO.getBackupPeriod()", 
					backupPeriodString);
		}
		return backupPeriod;
	}