September 2018

DiskWarrior 5.2

Support for Secure Boot, macOS 10.14 Mojave and APFS in Preview.

April 2018

DiskWarrior 5.1

Initial support for APFS.

December 2014

DiskWarrior 5.0

This 64-bit release was a complete rewrite with a new architecture resulting in significant speed improvements and improved repair and recovery. Added many new features and a new interface.

September 2011

DiskWarrior 4.4

Adds compatibility with external attributes and internal improvements for better and faster repair.

February 2011

DiskWarrior 4.3

Adds Mac OS X 10.7 (Lion) compatibility and numerous internal improvements for better and faster repair.

August 2009

DiskWarrior 4.2

Adds Mac OS X 10.6 (Snow Leopard) compatibility and additional repair capabilities. The update is also faster than previous versions and adds compatibility with the new 64-bit kernel.

January 2008

DiskWarrior 4.1

Adds Mac OS X 10.5 (Leopard) compatibility and additional repair capabilities. Among the new capabilities is the ability to repair damaged directory hard links (a new feature of Leopard for Time Machine backups).

December 2006

DiskWarrior 4.0

First Universal Binary release - now works with Intel and PowerPC Macs. The upgrade is also significantly faster than previous versions. DiskWarrior 4 includes an additional suite of file and folder tests, to fix problems before they cause users trouble. It also repairs invalid file permissions and identifies corrupted Preference (.plist) files.

July 2003

MasterJuggler 3.0

A complete rewrite of the professional font management tool, now for Mac OS X, adding many new features, such as drag and drop addition and management of fonts and the ability to preview fonts multiple ways in the MasterJuggler interface.

May 2003

DiskWarrior 3.0

Brings Mac OS X native directory rebuilding. Includes hardware monitoring component to warn of impending drive device failure.

January 2001

DiskWarrior 2.1

Compares old directory with new rebuilt directory and determines if there have been any changes to the number or contents of files and folders. Lists any differences it finds in the DiskWarrior Report by file, making it easier to see what files and folders need to be checked in the preview. If there is a system folder on the disk, ensures that the system folder is blessed. Ability to rebuild Mac OS X disks improved to accommodate the changes made in Mac OS X Public Beta. Checks System and Finder files for damage, eliminates a common cause of system crashes by checking custom icon files for corruption, and repairs the wrapper System file damage recently disclosed by Apple, allowing Macs with these disks to start up.

January 2000

DiskWarrior 2.0

Added DiskShield to make DiskWarrior the only utility to prevent disk directory damage.

November 1998


Only disk directory repair utility to rebuild, rescue, and optimize new disk directories on both Mac OS Standard (HFS) and Mac OS Extended format (HFS Plus) disks instead of trying to patch errors in the existing directory.

June 1998


First disk optimization program for HFS and HFS Plus disks under Mac OS 8.1.

January 1998


First third-party utilities for Mac OS 8.1 and HFS Plus. Only method available to convert disks from HFS to HFS Plus in place.

October 1997

DiskExpress Pro

Major feature additions including Power Mac native technology, AppleScript support, more powerful disk display, and integrated disk analysis tools.

June 1996

MasterJuggler Pro

Added Font Guardian and font gathering as well as Power Mac native technology to the venerable font management tool.

January 1993

Power To Go

Power management, security, and location settings for the first PowerBooks (Published by Claris Corp. - a subsidiary of Apple, Inc.).

January 1992

Power Utilities

MasterJuggler, DiskExpress, MultiDisk, MenuExtend (Apple Menu enhancer), DiskCheck (disk and directory diagnostic tool), ScreenEclipse (screen saver), and DiskFlash (disk activity indicator).

December 1989

DiskExpress II

Added the exclusive ability to optimize all Mac disks without restarting from a floppy, as well as automatic optimization in the background.

November 1988


First software-based partitioning for the Macintosh that didn't require partitions to occupy contiguous free space and allowed partition resizing.

August 1988


Replaced Font/DA Juggler, adding sounds, fkeys, application and window pop-ups, and many other features too numerous to list here.

August 1987

Font/DA Juggler

First font and DA management utility for the Macintosh.

January 1987


First to allow use of Apple // 3.5 ProDOS disks in Macintosh 800K drives.

August 1986


First disk optimization program for the Macintosh.



First dietary analysis and planning program for the Macintosh.



First programming framework for the Macintosh.

Chronological Release Dates of Alsoft Products

PlusOptimizer was the first disk optimizer available for Mac OS 8.1 and HFS Plus disks. It uses technology developed for DiskExpress Pro and PlusMaker to provide a fast, safe, and powerful solution for optimizing HFS Plus disks.

DiskWarrior was a radically new approach to resolving directory repair. Instead of patching the original directory, it quickly builds a new replacement directory using data recovered from the original directory thereby recovering files and folders that were lost and that no other program could recover. It also optimizes the directory for maximum directory performance, speeding up overall disk performance.

DiskWarrior 2.0 introduced the exclusive and innovative DiskShield to provide nonstop protection for Mac disks. DiskShield makes sure that directories are both updated and error-free.

The January 2001 introduction of DiskWarrior 2.1 added several new significant features that made DiskWarrior even easier to use while adding the ability to ensure that a startup disk is both bootable and reliable. It also improved DiskWarrior's ability to rebuild Mac OS X extended disks to accommodate changes made by Apple to these disks with the release of Mac OS X.

When DiskWarrior 3.0 was released in May 2003, it brought Mac OS X native directory rebuilding to DiskWarrior. Version 3.0 also introduced a hardware monitoring component to the application, providing users a warning if a mechanical failure of their drive devices seems imminent. This notification gives users a chance to back up any data on the drive before it becomes inaccessible.

When Alsoft introduced DiskExpress in 1986, it was the first and only disk optimizer for the Macintosh. It has always been the safest, most reliable, and most powerful disk optimization package available for Mac OS computers. It is the only disk optimizer that can optimize any disk, even the startup disk, at any time without having to restart from a floppy or CD. It uses advanced "Verify Reads and Writes" technology to maintain the integrity of files as they are optimized. The latest version, DiskExpress Pro, has received extremely high ratings from well-respected reviewers in the Mac community.

MasterJuggler is the most comprehensive font management utility on the market today. Originally known as Font/DA Juggler, MasterJuggler has now been rewritten in Cocoa to take advantage of the advanced features of Mac OS X. The latest version still retains its professional features, such as advanced set creation and management, font gathering, the ability to store fonts wherever a user likes, and Font Guardian technology to examine fonts. Font Guardian lets users know about corrupted fonts automatically and lets them take care of the corrupted fonts before they cause problems. It examines fonts for corruption and defects, notifies users of missing printer fonts, and notifies users of non-matching duplicate screen and printer fonts.

PlusMaker and PlusMaximizer were the first third-party utilities for HFS Plus (also known as Mac OS Extended format). PlusMaker converts Mac OS HFS disks to the new HFS Plus format without requiring users to initialize their disks and restore from backups, while PlusMaximizer gives them the smallest allocation block size available under Mac OS 8.1 or higher when initializing new disks.

Alsoft, Inc. was founded in 1984 by two former Apple employees to develop and market MacExpress®, the first programming framework for the Macintosh.

Alsoft is a leading developer of award-winning utility software that enhances the Mac OS. The company currently produces DiskWarrior® and MasterJuggler® Pro.

Since the beginning, our line of award-winning utilities has been well known and respected throughout the Macintosh community. Many of our products were the first of their kind, and most have features that remain Alsoft exclusives to this day.

A brief history of Alsoft
Alsoft Logo