“No matter how secure the ‘so-called’ excellent computer operating system Mac OS X is, users often come across issues like inaccessible volumes, corruption in volumes, fail to read/write access volumes, and the like. All such issues lead to data inaccessibility, and eventually, to data loss. Avoiding such issues; and hence, the data loss requires repairing the corrupt or inaccessible volume(s) at the earliest, which indeed requires a commercial volume repair application.”
When issues like volume corruption or inaccessibility are encountered, obviously everyone gets worried lines on his forehead, fussing over the consequences of the issue, which eventually lead to data loss. Since Mac OS X holds the crown of excellence, such scenarios were never supposed to come across on these computers at least. This indeed marks the vulnerability of Mac OS X to corruption and confirms that excellence still lacks a lot to meet the perfection.
Even though Mac OS X is the securest computer operating system available today, issues like disk or volume corruption or inaccessibility conquer the security factor and lead to data loss at the end of the day.
Causes of Volume Corruption
When one or more volumes of a Mac machine get corrupt due to virus infections or corruption in the volume header (caused by power failures, abrupt or forced system shutdown, and the like), it becomes nearly impossible to access data that can be crucial. However, apart from these, there are many other causes of volume corruption on Mac machines. These are discussed below:
File System Corruption
Mac OS X formats the hard drive and its respective volumes with the HFS+ file system (i.e. Mac OS Extended (Journaled)) that is intelligent enough to manage the data saved on individual volumes. However, it is enough prone to corruption due to virus/malware infections, improper system shutdown or power failures, and many other like causes.
Volume Header Corruption
Each volume of the hard drive associates a header (the size of this header is 1 KB) that contains its information, such as volume name & size, starting and ending sectors, used & free spaces, and more. As long as the header of a particular volume is fine, the user can read and write the volume as well as the data stored in it. Corruption in the volume header leads to volume inaccessibility and OS fails to read it.
Extent of Bad Sectors
The overall space (i.e. memory) of the hard drive is divided into blocks or sectors where each sector is intended to store a file. Based on the number of read/write operations performed, many sectors turn into bad or corrupt sectors and OS fails to read/write them. When the number of bad sectors in a volume goes high, it becomes inaccessible and leads to data loss.
Repair Corrupt or Inaccessible Volumes
When it comes to repairing corrupt or inaccessible volumes on Mac machines, two efficient options are there, i.e. using either Disk Utility or commercial Mac volume repair tool. However, selection of one of these tools depends on the user and his priorities. See how to repair a corrupt or inaccessible Mac volume:
Using Disk Utility
Disk Utility in Mac OS X is an efficient disk management tool, which most of the times proves its worth with its efficiency to fix the issues encountered. However, many users do not like Disk Utility as a preferred tool to manage the hard drive or to repair the volumes. Based on the expertise and due to the unavailability of volume repair tool, Disk Utility can be used to repair corrupt volume(s) on Mac in the following way:
Repair Disk Permissions
Each volume on the Mac system has a set of particular permissions associated with it. Corruption in the permissions of a volume prohibits the read/write operations on it. Follow the steps mentioned below to repair disk permissions:
- Launch Disk Utility and select the volume having corrupt access permissions in the left pane.
- With the right volume selected, click Repair Disk Permissions button in the right pane under First Aid tab.
While the repair process is running, make sure you let it finish without any sort of external interruption. As the repair process finishes, see the result in the result field.
Repairing one or more corrupt or inaccessible volumes is a long process and takes considerable time to finish. However, you must go for it in order to regain your data. See how to repair a corrupt volume on Mac:
- With the Disk Utility opened, highlight the corrupt or inaccessible volume in the list to the left.
- Click the Repair Disk button in the right pane under the First Aid tab.
As long as the repair process is going on, make sure it finishes without any interruption. If it fails due to some internal interruption, click Repair Disk button again and continue with it. On completing, see the result in the result field.
Disk Utility most likely repairs the corrupt or inaccessible volumes. However, the extent of corruption is a key factor on which the repair process is based. Read – How to fix “Invalid B-tree node size” Error with Stellar Volume Repair
Using Mac Volume Repair App
When Disk Utility fails to repair corrupt or inaccessible Mac volumes, use commercial Mac volume repair application, viz. Stellar Volume Repair – the award-winning volume repair tool for Mac OS X. See the key features of this professional Mac volume repair tool.
- Repairs corrupt Mac volumes efficiently
- Rebuilds corrupt or damaged Mac OS X directory
- Verifies and repairs volume permissions
- Provides Rollback option to revert changes
- Creates Bootable USB to repair boot volume
- User-friendly and interactive interface
This volume repair tool allows rebuilding the corrupt or inaccessible Mac volumes in the following easy steps:
- Launch Stellar Volume Repair and click Continue button on the home screen.
- Amongst the volumes listed to the left, select the corrupt volume and click Rebuild button in the toolbar.
- Clicking the Rebuild button starts rebuilding the volume and ends with one of the following three scenarios:
- Selected volume is fine and no need to repair it
- The volume is repaired successfully
- The volume is severely damaged or corrupt, and therefore cannot be repaired. The Rollback option lets you go back to the previous stage
Note: The software does not support nor repairs exFAT file system based volumes.
Rebuild Boot Volume
Alike secondary volumes, primary or the boot volume on Mac also gets corrupt sometimes. In such a state, Mac machine fails to boot. This volume repair tool allows you rebuild the boot volume as well. See how to do it:
- Boot from the bootable USB created using this software and you see the software launched.
- In the list of volumes shown to the left, select the corrupt on, and then click the Rebuild button in the toolbar.
- With the repair process going on, following are three scenarios:
- Selected volume is fine and no need to repair it.
- The volume is repaired successfully.
- The volume is severely damaged or corrupt, and therefore cannot be repaired. The Rollback option lets you go back to the previous stage.
The Bottom Line
The selection of a volume repair tool not only makes the steps to follow different, but it also affects the process as a whole. Thus, make sure the tool selected is reliable and got the efficiency required to carry out the job efficiently.