Backup File Contains Unrecognized Data - Version 5.4 “Backup file contains unrecognized data and cannot be used” - This error message pop ups on your computer screen when NTBackup.exe utility finds corrupted files. In this condition you can't be restored it without getting external tool. And if you have decided to do this then we suggest you to use BKF recovery tool that is an expert approach to recover corrupt BKF file. Backup File Contains unrecognized data error is mostly found when BKF file is damaged & corrupted due to operating system corruption, CRC errors, virus attack and incomplete backup process when system is suddenly shutdown. Download demo version to view the contents of corrupt or damage BKF file which display only the preview of the recoverable files and folders. If you satisfied with our demo version, then purchase full version at $89.