Repairing your Mac's hard drive directory with DiskWarrior

When hard drive corruption occurs, your Mac may behave strangely (e.g., loooong pauses in Finder or Open/Close dialogs). In severe cases your Mac will refuse to startup. When Apple's Disk First Aid (a feature of the Disk Utility) fails to fix a corrupted drive, turn to DiskWarrior.

Alsoft's DiskWarrior is the hard drive repair champion. Have it on hand before problems arise.

When should I run DiskWarrior?

These are good times to take a break and run DiskWarrior:

  • Before installing a Mac OS X upgrade (e.g., Yosemite to El Capitan) or update (e.g., 10.11.1 to 10.11.2).
  • When your Mac does not complete startup, i.e., the desktop never appears.
  • When two or more applications start behaving strangely.
  • When you want assurance your hard drive is in good condition.

If DiskWarrior repairs a serious error (see "Review DiskWarrior's report" below), it typically has also resolved the problem(s) that prompted you to run it.

Even if DiskWarrior finds no serious errors, it's helpful to know hard drive corruption is not the source of any current problems.

DiskWarrior 4.4 and DiskWarrior 5

This tutorial, which was created for DiskWarrior 4 users, has been expanded to cover both DiskWarrior 4.4 and DiskWarrior 5.

DiskWarrior 4.4 can be used on Macs introduced before June 11, 2012, i.e., Macs that can run Mac OS X 10.6.8. Newer Macs require DiskWarrior 5.

DiskWarrior 4.4 was distributed on DVD. DiskWarrior 5 is distributed on a USB flash drive. It requires a second USB flash drive (16 GB or larger) on which is builds a bootable DiskWarrior volume that's customized for your Mac.

Most sections of this tutorial apply to both DiskWarrior 4.4 and 5. Version-specific sections have a "DW 4.4:" or "DW 5:" prefix on the section heading. The screenshots were captured from DiskWarrior 4; DiskWarrior 5 users will notice cosmetic differences.

Print this tutorial

If you're reading this on the Mac that's about to run DiskWarrior, print the PDF version of this page to have it handy while DiskWarrior is repairing your drive.

Note: Resist the temptation to print this Web page from your browser – the screenshots get separated from the related instructions.

DW 4.4: Restart from the DiskWarrior DVD

If your Mac starts up from its internal hard drive, DiskWarrior can't dismount the drive in order to repair it. So you must start up your Mac from the DiskWarrior DVD:

  1. Insert the DiskWarrior DVD into your Mac and wait for the disc to appear on your Desktop.
  2. Choose "Restart" from the Apple Menu.
  3. After the screen goes blank, hold down the "C" key until the Apple logo appears on the screen. The "C" must be pressed before the end of the startup "chime."
  4. Wait 5-10 minutes for your Mac to start from the DVD. Starting Mac OS X from a DVD is a lot slower than from the internal hard drive.
  5. Click the "Agree" button on when the DiskWarrior license window appears.

Notes:

Some newer Macs with wireless keyboards have timing issues when starting up from any DVD. Instead of pressing the "C" key immediately upon start up (step 3 above), press the "Option" key. This will bring up the Startup Manager which will allow you to choose the DVD as a startup disk. If your wireless mouse is not working in the Startup Manager, use the right- or left-arrow keys to choose the DVD, and then press the "Return" key to continue starting up.

If your Mac fails to start up from the DiskWarrior DVD, it's likely the version of Mac OS X on the DVD does not support your newer Mac. In that case, you should contact Alsoft Sales to order an updated DVD.

DW 4.4: Wait for DiskWarrior to scan for hard drives

DW 5: Restart from your custom DiskWarrior Recovery flash drive

If your Mac starts up from its internal hard drive, DiskWarrior can't dismount the drive in order to repair it. So you must start up your Mac from your custom DiskWarrior Recovery flash drive:

  1. Insert the DiskWarrior custom flash drive into your Mac and wait for the "DiskWarrior Recovery" icon to appear on your Desktop.
  2. Choose "Restart" from the Apple Menu.
  3. After the screen goes blank, hold down the Option key until the Startup Manager icons appear on the screen. The Option must be pressed before the end of the startup "chime."
  4. Use the right or left arrow keys to move the white arrow below the DiskWarrior Recovery drive as shown above.
  5. Press the Return key to startup your Mac from the DiskWarrior drive. A white Apple icon and progress bar will appear on your screen.
  6. When the language selection screen appears, choose English to proceed.

DW 5: Launch Alsoft DiskWarrior

  1. Select "Alsoft DiskWarrior" in the list of OS X Utilities.
  2. Click "Continue" to launch DiskWarrior.
  3. Click the "Agree" button on when the DiskWarrior license window appears.

Select the hard drive to be repaired

Select the drive you wish to repair from the menu of all available drives.

DW 4.4: DO NOT select your Time Machine backup drive. DiskWarror 4.4 cannot repair a Time Machine drive. (DiskWarrior 5 can repair a Time Machine drive.)

Begin the repair

Click the "Rebuild" button to begin repairing the drive.

Wait for DiskWarrior to complete the rebuild

DiskWarrior's reports the progress of rebuilding the hard drive directory. The top progress bar corresponds to the 10 rebuild steps; the bottom bar shows the current step.

The 10 steps will take from 5 to 30 minutes (or more) depending on the number of files on the drive.

Review DiskWarrior's report

Red text indicated errors that have been repaired.

Repairs to icons, dates and file attributes are useful but typically do affect overall system performance.

"Incorrect values in the Volume Information were repaired" (or a similar message) indicates the disk directory was seriously damaged. Your Mac will perform much better after this type of repair.

Replace the drive directory

Wait for DiskWarrior to create a new disk directory

DiskWarrior takes a minute or so to replace the disk directory.

If DiskWarrior reports there is not enough free space on the drive to do a fail-safe replacement, it's actually safe to tell it to proceed.

Don't Save the report

If the DiskWarrior report included any red text, DiskWarrior will offer to save the Step 10 report. Click "Don't Save" because there's no need fior this report once the drive has a new, clean directory.

Repair additional hard drives

If your Mac has additional hard drives (other than your Time Machine backup drive), it's a good idea to repair each of these drives.

Quit DiskWarrior to Restart

Choose "Quit" from the "DiskWarrior" menu (top menu bar) to Restart your Mac from its newly repaired internal hard drive.

DW 5: Then choose "Quit" from the "Utilities" menu to perform the Restart.

DW 4.4: Eject the DiskWarrior DVD

After Restart, your DiskWarrior DVD will mount on your Desktop. Dragging the DVD icon to the Trash will pop up this dialog window. Simply press the "Eject All" key.

You can avoid this dialog by pressing the Eject key on your keyboard (instead of dragging the DVD icon to the Trash).

DW 5: Eject the DiskWarrior Recovery flash drive

After Restart, your DiskWarrior Recovery drive will mount on your Desktop.

  1. Drag the DiskWarrior Recovery icon to the Trash.
  2. Wait for icon to disappear before removing the flash drive.