Project settings > Project options

Delete unused files in destination folder: You can choose to clear the destination directory before, after the backup process or format disks automatically. This way you can prevent running out of diskspace or to generate an exact copy of the source directory. If you choose to clear it afterwards, it is renamed to a temporary folder and deleted after the backup has been successful

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Check for open files	Check that all files in backup set are not opened by another application .
Include empty subdirectories	Also pack directories with no files into the archive.

Page url: http://manual.backupx.com/index.html?project_options.htm