With Windows NT, Microsoft introduced Windows Backup (also known as NTBackup), and it was subsequently included in versions of Windows up to and including Windows 2000, Windows XP and Windows Server 2003. It can back up to tape drives, using the Microsoft Tape Format (MTF), or to disk using the closely related BKF file format.
Support for Windows Backup was dropped in Vista but Microsoft introduced the Windows NT Backup Restore Utility for both Windows Vista/Windows Server 2008 (supporting disk and tape backups) and for Windows 7/Windows Server 2008 R2 (supporting disk backups only).
If you just need to restore a MTF/BKF file, the Microsoft-provided software above is probably the best option. However, if (like me) you don’t have a Windows computer handy, or you want to convert the backup into a format more likely to be readable a few years later, they are not ideal. That is why I tried out the mtftar utility, which converts MTF/BKF files into the extremely well-supported TAR file format.
Unfortunately, mtftar appears unmaintained since 2007 and in particular, it doesn’t build on Mac OS X. That’s why I set out to fix it. In case this is of help to anyone else, I have made the modified GPL’d source available on GitHub (diff). It works well enough for me, but use at your own risk.