Repair Macintosh HD with Disk Utility and Safe Mode

If you are concerned about your Mac drive as it is continuously showing issues while accessing the operating system or stored files, then there could be either mechanical or logical issues with the hard drive. In order to repair Macintosh HD, first you need to diagnose the problem and try to resolve the issues with disk utility.

Here are he steps you can follow to identify the actual issues along with most possible way to resolve them:

Using Disk Utility:

Mac provides a Recovery Mode that lets you to diagnose the hardware issues, restore Time Machine backups, manage hard drives, and even reinstall OS X itself. Therefore, Recovery Mode should be your initial steps to diagnose and resolve the Mac drive problem.

1. To use Recovery Mode, reboot or start the Mac while holding the Command and R keys as soon as you hear the startup sound. 
2. Keep holding the key until you will not be able to view a screen along with multiple Mac utilities. 
3. Here, select ‘Disk Utility’ when it opens and click on your hard drive and then ‘Repair Disk’. Now, wait till the computer completes its process. 
4. After successful process exit the installer and also Quit Disk Utility and go to Utilities > Start-Up Disk.
5. Now, select the disk with Mac OS X and click Restart

After successful process the result either resolves your system problem or the hard drive might show failure indications.

What if you don’t have Mac OS install DVD?

In case the Mac OS install DVD is not available right now but you have access to another Mac and a firewire cable then you can also try to boot the Mac in Target Disk Mode. To do this follow the below steps:

1. Turn on your targeted Mac machine while holding the T key
2. A gray screen will appear with a large moving Firewire logo
3. Now, you can connect the two Mac systems via firewire cable and then boot the healthy Mac while holding the Alt/Option key as described above
4. The sick Mac’s hard drive in target disk mode will appear as a boot option on your healthy computer. Select it and initiate the process
5. If you will be able to boot through the selected drive successfully, you can try again to run Disk Utility from Applications->Utilities and verify/repair the hard drive
6. If this works, the again try to reboot your computer normally and check if the problem has been solved.  

Booting the Mac in Safe Mode

When you boot your Mac in safe mode it will automatically attempt some disk repair measures. Here are the steps to start up into standard Safe Mode

1. Shut down the Mac
2. Now, turn on the system by pressing power button
3. Immediately hold the Shift key after the startup tone
4. Hold the Shift key until the Grey Apple icon and the progress indicator doesn’t appear

Note: In order to start up a Mac machine into Safe Mode with display of the progress in a command line UI, follow all above mentioned steps except hold the Command and V keys along with Shift.

Alternative solution

If nothing worked for you, then possibly your Mac has a severe problem that needs a special treatment to resolve. In order to do that a professional drive repair software should be the preferred choice of professionals. You can repair corrupt drive directory with Stellar Volume Optimizer software. Yes, it also repairs bad disk permissions and creates bootable media to repair Mac startup drive.

All of the above explained solutions might take you to data loss situation if anything goes wrong; therefore, backup is the most preferred solution you should always follow if you can before performing any data recovery method. In case, you your hard drive is having these issues due to any reason then it is better to go with a professional method instead of trying multiple repair trials as they might end up with a data loss situation.