Convert NBF to EPUB

As far as we know, there doesn't seem to exist a way how can easily convert NBF Backup NOW! archive to a digital EPUB book, which is what nbf to epub conversion would be. If you are trying to recover .epub files from the .nbf backup, you need to use the Backup NOW! recovery software.

Simply put, it is impossible to convert NBF to EPUB directly.
Thus, there is no so-called nbf to epub converter or a free online .nbf to .epub converter to be found.