Are you unable to start your Macintosh system, of late? Is this behavior is happening intermittently? Then, there is a very strong possibility that this is happening because of corruption in the Macintosh hard drive. The corruption can happen because of various reasons including power outages, critical file system files missing, abrupt system shutdown, etc. There are various methods that can be used to start the system. If none of these methods work, then you should use a third-party Mac data recovery software to perform data recovery in Mac systems.
Consider a situation in which you have a Macintosh-based system, which is not starting when you try to boot it. It is just displaying a blue screen without any error message.
Cause:
The root cause of this startup related problem is the hard drive corruption, which is disabling you from starting the system.
Resolution:
To tackle this situation, you should perform the following methods, preferably in the given order:
Booting from a different device: You should try to boot the Mac system using a removable boot device like USB drive, Mac OS X setup DVD, etc. To start Mac system using a setup DVD, the following steps are required:
Insert the DVD and hold the 'c' key after restarting the system.
You can, then, use the in-built First Aid utility to verify and repair hard drive.
Safe Mode: You can start the system in the Safe Mode by holding the 'Shift' key after restarting the system. It verifies the directory structure of the volume, and repairs it, if necessary. After logging in the system, you can use the First Aid utility to further repair the Mac hard drive.
Single User Mode (fsck): You can access the system by logging into command-line prompt using the following steps:
Restart the system and hold the 's' key.
Type the following command in the command-line prompt and press the Enter key to use the 'fsck' tool on the hard drive:
/sbin/fsck –fy
After a while, the file system is verified and repaired as the following message box is displayed.
** The volume xxxx appears to be OK.
If you receive the following message as well, then run the command again til you get the previous message.
***** FILE SYSTEM WAS MODIFIED *****
If the Mac system still remains inaccessible, then you should recover the data using a third-party Mac recovery software before reinstalling the operating system. Such Mac file recovery tools are non-destructive in nature that do not overwrite the existing file during the recovery.
