Your Mac or MacBook relies on its internal disk to supply the storage capacity that makes it a useful computing platform. Without the data stored on the disk, your laptop would be little more than a high-powered calculator. The disk, along with the machine’s CPU, are the two most important components involved in designing a computer. Without either one of these critical elements, your computer would provide no real value except as a paperweight or desk ornament.

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Modern drives are more resilient than those used in previous generations of personal and business computers. The introduction of SSDs has minimized some of the mechanical issues faced by more traditional hard drives. You might go through life using multiple computers and never experience a disk failure. You also might win the Powerball. Probably neither will happen and at some point, you will have to handle a disk failure.

Reasons Your Mac Disk Might Fail

Disks can fail for a variety of reasons. Your machine may be equipped with either a Hard Disk Drive (HDD) or a Solid State Drive (SSD). SSDs are faster and employ an electrical grid to store data. These are the kinds of drives you will find in most modern laptops including MacBooks. They have fewer moving parts than an HDD which makes them less susceptible to mechanical problems. HDDs use mechanical means to read and write data to the disk and these parts can wear out over time, causing issues and the eventual failure of the storage device.

Here are the most common reasons that a drive might fail:

  • Mechanical Failure – HDDs and SSDs can both fail due to problems experienced by their internal components. The electrical blocks used by an SSD can wear out and lead to sudden failure. HDDs may give more warning when having mechanical difficulties, as you may hear strange sounds emanating from your disk indicating the disk may soon fail. Choose to ignore these warnings at your own risk.
  • Electrical damage – Power surges or the discharge of static electricity can cause a drive failure.
  • Moisture or humidity – Exposing an HDD or SSD to extremely high humidity or moisture can destroy the drive.
  • Excessive heat – Heat can cause your drive to fail. This can occur due to operating the machine without proper cooling or leaving a laptop in a hot vehicle for an extended length of time.
  • Physical shock and impacts – Dropping the drive can cause a drive failure. These are precision devices that are not designed to be thrown around.

These dangers can affect your external drives as well as those inside your computer, so care should be taken with all of your storage devices.

Predicting a Disk Failure on Your Mac

The ability to predict a disk failure would save a lot of time and trouble, as you could take preventative action before any data loss occurred. While not foolproof, there are some indications which you should consider when determining the health of your computer’s disks.

  • Unexpected computer or application crashes.
  • Slow performance when starting your computer or opening applications.
  • A sudden increase in the number of missing files or corrupted data.
  • The aforementioned strange sounds coming from the drive. An HDD will often give a hint that it is having trouble by producing a grinding or spinning sound as it tries to access data.

S.M.A.R.T. stands for Self-Monitoring, Analysis, and Reporting Technology. It is a feature of modern disk drives and can be used to help predict drive failure. You can obtain information such as the wear level of an SSD drive which might indicate it is nearing the end of its serviceable life. S.M.A.R.T. is not perfect and will not always alert you to impending drive failure, but it can alert you to issues that you can address before disaster strikes.

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Third-party tools such as Disk Drill can be used to monitor the S.M.A.R.T. status of the drives on your Mac computer. It provides a window through which to gain some insight into the health of your drive and be better prepared if it appears to be experiencing problems.

Detecting a Disk Failure

Way #1

Unfortunately, detecting a disk failure can be a painful and simple process. One thing to keep in mind is that some of the same problems you might experience from a failing disk can be caused by a malware infection. You would do well to run a full scan on your machine and determine that malware is not the root cause of your problems before accepting the fact that you may have a bad disk.

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Way #2

Your machine’s BIOS may display error messages related to disk problems encountered when attempting to boot your machine. Receiving these messages on consecutive reboots of your computer indicates that you probably have a fairly serious disk problem.

Some messages you are likely to see include:

  • Hard Disk Error
  • Operating system not found
  • Invalid system disk
  • Disk boot failure

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Way #3

When a drive has indeed failed you may be unable to boot your computer. If it does start, performance might be downgraded and your machine will often freeze and crash. You may have no choice but to try to salvage the data that resided on the disk. Disk Drill enables you to recover data from a damaged disk by scanning it at the sector level to reconstruct and save your files.

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Methods for Preventing a Disk Failure on Mac OS X

There are several actions you can take if you suspect that your disk is having issues and may soon fail. They will not necessarily prevent the failure but will leave you in better shape to recover and minimize the impact of the damaged disk.

#1. Backup your data

Protecting your data against an eventual disk failure just makes sense. You should already be performing regular backups if you value your data, but in the case of warning signals being sent from the drive, extra precautions should be taken. You need to be careful when attempting to create a backup of a potentially damaged disk. It may not be able to withstand the rigors of many more backups.

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The best course of action is to first create a disk image backup to be used for data recovery purposes if the drive does fail. Disk Drill contains this functionality and can create a disk image from which it can restore all of your files.

#2. Use the Mac’s Disk Utility tool

This tool can help extend the life of your drive by fixing problems before they become critical. Running the First Aid process from within Disk Utility can repair file permissions or issues that are causing the drive to misbehave. It will alert you to an impending drive failure which indicates that you need to create a backup of your data as soon as possible.

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These techniques will not always be sufficient to prevent your drive from failing. You may have to deal with the sad reality of a bad disk.

Recovering Your Mac From a Disk Failure

Despite your best efforts, your drive may indeed fail and leave you scrambling for a way to get your data back. Here are some options for you to consider when faced with this dire situation.

Option #1

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In the case of external drives or if the device can be removed from your machine, you can try using in another computer. It may not function properly for the purpose of starting your system, but may still operate sufficiently well to allow you to extract the data from it through the macOS. When following this route, move the data off of the problem disk immediately, as the longer you delay the potential increases for a total failure.

Option #2

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You can engage a data recovery service to attempt a rescue of the drive’s information. This is not an inexpensive option and will mean you are without the drive for some time. You are also trusting the recovery service with any sensitive data that is on the disk which may not be to your liking.

Option #3

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As long as the drive can be accessed in some way, Disk Drill hard drive recovery tool can help you recover with a minimum of lost data. The tool will scour the disk and recover its data to a new and more stable location. You may want to use a disk image backup which can be created with Disk Drill to restore your data without adding additional stress to the physical device. Using this professional data recovery tool is cost-efficient and eliminates the need to send your drive out to a data recovery service.

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Sometimes there is no technique that can help you recover from a failed drive except to restore the data from backups that were previously taken. You probably have heard that backing up your data is an important part of using a computer, and now you can see why. Start backing up your data today if you are not already doing so and have a fallback plan to recover from a failed disk. It might be the only way to save the valuable information stored on your Mac.

Jeff Cochin

Jeff Cochin is a data management and recovery expert. He also serves as a technical writer, testing and reviewing tech solutions in various fields. Jeff Cochin is a professional data management, warehousing and recove...

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Approved by
Brett Johnson

This article has been approved by Brett Johnson, Data Recovery Engineer at ACE Data Recovery. Brett has a Bachelor's Degree in Computer Systems and Network, 12 years of experience.