Disk First Aid is a utility program that verifies the directory structure of any Mac OS Standard (HFS) or Mac OS Extended (HFS Plus) format disk.
If imperfections are found within a disk (or "volume"), Disk First Aid can be used as a first step to correct them. If Disk First Aid cannot be used to correct imperfections, other utility programs or repair methods may be used. The following table lists conditions that can be repaired using Disk First Aid:
- Disk volume
- Extent B-tree
- Extent File
- Catalog B-tree
- Catalog File
- Catalog Hierarchy
- Volume Info
- Search for locked volume name
You can save the results of a verification or repair scan as a SimpleText document.
Disk First Aid cannot scan for deleted files or folders on a volume. There are third-party products that perform these tasks, however.
For related information on Disk First Aid and Mac OS disks, please see the following articles:
Article 13628: "Disk First Aid: What to do When It Finds an Error"
Article 19516: "Mac OS: Technical Overview of Disk Volume Structures"