Fix volume corruption on Mac OS X
Fix volume corruption on Mac OS X.
Volume corruption can occur from a variety of causes. To fix this problem, the best way is to reinitialize the drive, then reformat. If a backup of the data is not available, data recovery should be done first. The reformatting process will erase the disk permanently, so it must be recovered prior to attempting to fix anything.
Once the data is recovered, proceed with the process below to attempt to fix the drive.
IMPORTANT NOTE: Following the procedure below will ERASE ALL DATA on the drive. Prior to following these directions, verify important data is stored securely on a different storage device.
Begin by opening Disk Utility. This program is found in Applications, then in the Utilities folder. In the walkthrough below, we will be fixing a 20GB hard disk. All computers will look slightly different.
The disk is listed on the left side. Click the entry that says the size (18.6GB in this case.) Choose the Partition tab along the top.
Change settings to match the example. Volume Scheme should say 1 Partition, and Format should say Mac OS Extended (journaled)
Click the Options button.
From the following list, set the appropriate option for the computer the drive will connect to.
- GUID for Intel Macs
- Apple Partition Map for PowerPC Macs
- Master Boot Record for compatibility with Windows XP computers. This options is for compatibility between Macs and PCs. If that is not necessary, do not choose this option.
Click OK when the proper option is selected. Doing so will return the display to the Disk Utility window. Click Apply.
In fewer than 30 seconds, the drive will be reformatted and repartitioned. The next step is to run a test on the drive to look for other problems.
Choose the drive again, and choose the Erase tab.
Choose the desired format in the drop-down near Volume Format. In most cases, Mac OS Extended (Journaled) is best.
Set the Name option to the name the desktop icon should be. Choose a familiar name, as this will be the way the drive is identified on the desktop.
Click the Security Options button.
Choose the option of Zero Out Data, then click OK. When back in the Erase window, click Erase in the bottom right of the window.
Another warning screen will appear. Click Erase when ready. This will take several hours, and generally make the computer unusable during the process. Ensure that is practical prior to starting this final process.