FastBack Plus

Overview
FastBack Plus (FB+) was backup software available for MS DOS and Macintosh systems from ~1987 to ~1992.

Its primary competition was PC-Fullbak by Westlake Data Corporation, which used both a proprietary disk-sector and file system format (i.e. the backup disks can't even be copied by conventional means).

Although the backup disks created by FB+ are readable from modern systems, the files they contain (typically one file per disk) appear to be compressed in a proprietary format which cannot be decoded by any standard tools. Recovering data from disks created by FB+, then, generally requires running FB+, which has its own set of problems.

Running FastBack Plus

 * First, this presumes that you have a copy of it to run. It appears to be freely available from here, though I have not tried the download.
 * Second, it crashed when I tried to run it from Windows 98. It may be that it would work fine if I booted to command-line only.
 * Third, it will only restore files to their original locations -- but you can select which files to restore, and skip over any files in the root folder.
 * (Not sure about this) Fourth, you must have the first disk in the set -- even if the file you want is on a different disk -- because that is where the index is stored. (The index file must be readable, too.)