Disk Manager is a discontinued software (that was a popular 1980s and 1990s) and documentation package for MS-DOS and PC DOS computers, useful for self-installing personal computer hard disks. It was written by Ontrack, a company that is now part of KLDiscovery.

Installation covered different aspects:

explaining personal computer hardware concepts
documenting switches of many of the existing disks
putting into place custom device drivers which circumvented BIOS limitations, notably those related to maximum disk or partition size and logical block addressing
providing testing and informational utilities
Drivers could be either DOS-type, or replacement master boot record code.

Diskettes with Disk Manager were provided by some disk manufacturers (e.g. IBM), in custom OEM versions, supporting all of their models.

Not long after launching in 1985, Ontrack also started providing computer disk data recovery services as Ontrack Data Recovery.
Tell me about a Disk Manager
Disk Manager is a discontinued software and documentation package for MS-DOS and PC DOS computers.  It was written by Ontrack, a company that is now part of KLDiscovery. Diskettes with Disk Manager were provided by some disk manufacturers in custom OEM versions, supporting all of their models.