mtftar is a utility that can read data stored in BKF files generated with Windows NTBackup program.
The original source is: https://github.com/geocar/mtftar
However, on Debian 9 in 2018, this code currently produces errors such as:
MTF error out of order mtftar (files before directory saw 4 while expecting limit of 0)
This does not look like a tar archive
To avoid these error messages, download and make the version from here: https://github.com/sjmurdoch/mtftar
To search for files or folders:
mtftar < source.bkf | tar tvf - | grep SomeName
To extract files:
mtftar < source.bkf | tar xvf - 'C:/Documents and Settings/User/Documents'
This will extract the folder with full path to the current directory. If a folder name is not specified all files will be extracted.