When this option was not explicitly turned off when starting a project directly from the project administration, a detailed execution log will always also be created when processing a project, in which it is clearly shown what was done with which data source and if there have been any errors in doing so. In addition, a backup is always created when the data from a data source have been directly modified or deleted. It contains all the modified or deleted records and is created as a text file, similar to an archive file. With Excel files, a copy of the source file is created as a backup. The application data directory, in which the logs and backups are stored, can be moved in the Options. Despite this security mechanism, you should still make regular backups of your data, regardless of BatchDeduplicator.