How to Fix Extent Allocation Overlapping in Mac OS X

How to Fix Extent Allocation Overlapping in Mac OS X

Disk inconsistency and file system problems are very common in every computer operating system, including Mac OS X. To handle such situations and check file system integrity/consistency, Mac OS X provides Disk Utility and fsck tools. Both these utilities are able to detect hard drive and file system related problems and even fix minor issues. But in some cases, these tools can not help you to resolve the problem and you come across data loss circumstances. In order to retrieve lost data from Mac hard drive, you are required to opt for Mac File Recovery solutions through appropriate tools.
In a practical scenario, when you run Disk Utility or fsck command on Mac OS X hard drive to check it for errors, you might come across the following error message:

“overlapped extent allocation”
The disk checking process gets terminated with above error message and the hard drive errors remain unresolved. It renders all your data inaccessible. In order to retrieve data in such situations, you need to find out the cause of this problem and perform Mac Recovery by fixing it.
Root of the issue:

As stated in the above error message, problem is caused due to overlapping of allocation space. When this error message takes place in Mac OS X, it means two files are taking the same disk space. Thus, it is certain that one file among them would be deleted. Solutions of the above problem exist, but you need to ensure that you do not lose more data. Thus, it will be a wise step to recover lost data first and then fix current issue.
Resolution:

You can sort out this problem by using any of the below solutions:

Perform Erase and Install installation of Mac OS X using installation disk. You should always back up your critical data before you go for it.
Delete affected files and then restore them from backup. In case backup is not available, you will face data loss.
To retrieve data from affected Mac OS X hard drive, Mac Recovery Software are required. These are advanced and effective third-party applications, which use efficient scanning techniques to perform in-depth scan of entire hard drive and extract all lost, missing, and inaccessible files from it. The applications have rich graphical user interface and thus let you perform easy Mac File Recovery on your own.
Stellar Phoenix Macintosh Data Recovery is the most comprehensive and efficient tool to ensure absolute recovery of lost data. It is designed for Mac OS X 10.6 Snow Leopard, 10.5 Leopard, 10.4 Tiger, and 10.3.9 Panther. The software recovers data from HFS, HFS+, HFSX, HFS Wrapper, and FAT file system volumes.