Disk First Aid is a free
software utility
Utility software is software designed to help analyze, configure, optimize or maintain a computer. It is used to support the computer infrastructure - in contrast to application software, which is aimed at directly performing tasks that benefit ord ...
made by
Apple Inc.
Apple Inc. is an American multinational technology company headquartered in Cupertino, California, United States. Apple is the largest technology company by revenue (totaling in 2021) and, as of June 2022, is the world's biggest company b ...
that was bundled with all computers running the
classic Mac OS
Mac OS (originally System Software; retronym: Classic Mac OS) is the series of operating systems developed for the Macintosh family of personal computers by Apple Computer from 1984 to 2001, starting with System 1 and ending with Mac OS 9. The ...
.
This tool verifies and repairs a limited number of
directory structure
In computing, a directory structure is the way an operating system arranges Computer file, files that are accessible to the user. Files are typically displayed in a hierarchical tree structure.
File names and extensions
A filename is a string use ...
problems on any
HFS or
HFS Plus
HFS Plus or HFS+ (also known as Mac OS Extended or HFS Extended) is a journaling file system developed by Apple Inc. It replaced the Hierarchical File System (HFS) as the primary file system of Apple computers with the 1998 release of Mac OS 8.1 ...
hard disk
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
or volume.
Disk First Aid is a very simple tool, with it only being able to detect and repair directory damage
and many books are critical of its sometimes inaccurate reporting of errors, and often suggest to run the tool more than once to ensure a consistent result.
Disk First Aid is located in
Applications:Utilities:Disk First Aid.
The classic Mac OS provides an option to run Disk First Aid on startup, although it has been reported that it provides little gain and sometimes can amplify a problem.
Its capabilities were incorporated into
Disk Utility
A disk utility is a utility program that allows a user to perform various functions on a computer disk, such as disk partitioning and logical volume management, as well as multiple smaller tasks such as changing drive letters and other mount poi ...
in
macOS
macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and lapt ...
.
Situations to use the tool
One source suggests that disk utility should be used when there are:
* Frequent
system crashes,
* Disappearing files,
* Files changing size,
* Problems copying files from one place to another,
* Problems saving files,
* Cryptic error messages,
as well as for general maintenance every 6 months.
Analysis
Disk First Aid has built-in capabilities to check for damage to:
*
Partition Map,
*
Device Driver
In computing, a device driver is a computer program that operates or controls a particular type of device that is attached to a computer or automaton. A driver provides a software interface to hardware devices, enabling operating systems and ot ...
,
*
Boot Blocks,
*
Master Directory Block,
*
Volume Bitmap,
*
Catalog File,
*
Extents File,
*
Finder Attributes,
*
Disk volume,
*
Extent B-tree,
*
Catalog B-tree,
*
Catalog Hierarchy,
* Volume Info,
* and to search for locked volume name.
After analyzing the disk directory, Disk First Aid determines whether it is able to repair any damage that was detected. The utility can commonly only fix problems associated with the catalog/extents files and the volume bitmap.
Commonly, the program reports that there is an error, but cannot fix it.
See also
*
List of data recovery software
In computing, data recovery is a process of retrieving deleted, inaccessible, lost, corrupted, damaged, or formatted data from secondary storage, removable media or files, when the data stored in them cannot be accessed in a usual way. The dat ...
Notes
{{reflist
Classic Mac OS
Classic Mac OS-only software made by Apple Inc.
Hard disk software