How to Tell if Your Hard Drive Is Failing

The most common signs of a failing hard drive

A mechanical hard drive, also known as an HDD, contains spinning platters and read heads that move extremely close to their surface. These mechanical components can wear out, suffer damage after a shock or begin struggling to read certain areas of the drive.

Failure is not always immediate. A drive may initially become slower, produce occasional errors or disappear intermittently before becoming completely inaccessible.

One symptom on its own does not necessarily mean that the drive is about to fail. Several symptoms appearing together, or a problem that is quickly becoming worse, should be taken much more seriously.

Unusual noises: clicking, grinding or repeated attempts to start

A mechanical hard drive naturally produces a faint spinning sound and some movement from the read heads. What should concern you is a new, loud or repetitive noise.

• regular clicking or repeated ticking noises;
• attempts to spin up followed by an immediate stop;
• grinding or scraping sounds;
• the drive repeatedly speeding up and slowing down;
• a new noise appearing after a fall or impact.

Files becoming unreadable or corrupted

One file refusing to open does not automatically mean that the hard drive is faulty. The file may have been saved incorrectly, moved or damaged by software.

The situation becomes more concerning when several unrelated files begin showing problems, particularly if you notice:

• photos that only display partially;
• documents that suddenly generate errors;
• folders that are extremely slow or impossible to open;
• filenames becoming unreadable;
• errors while copying files to another drive;
• files disappearing without being deliberately deleted.

These symptoms may be caused by areas of the drive that have become difficult or impossible to read. A sector is a small area used to store data. When an increasing number of sectors can no longer be read reliably, the drive may slow down considerably while repeatedly trying to access them.

The computer freezes whenever the drive is being used

A failing drive can temporarily freeze the entire system. Windows waits for a response, the drive repeatedly attempts the same read operation and the computer appears to stop responding.

• File Explorer stops responding when you open a folder;
• Windows suddenly takes much longer to start;
• a file transfer repeatedly freezes on one particular file;
• Task Manager constantly shows 100% disk usage with very little data actually being transferred;
• the computer freezes as soon as an external drive is connected.

Disk usage at 100% can also be caused by Windows Update, antivirus software, insufficient RAM or too many background programs. To distinguish a drive fault from the other common causes of a slow computer, you need to consider all the symptoms rather than relying on one figure in Task Manager.

A drive that disappears or is only detected occasionally

An internal or external drive that disappears from Windows, the BIOS or Disk Utility on a Mac may be failing, but hardware failure is not the only possible explanation.

Before assuming that the drive itself is dead, it is also worth considering:

• a faulty USB cable;
• an unreliable USB port;
• a failed external drive enclosure;
• insufficient power;
• a loose SATA cable;
• a damaged connector;
• a driver or file-system problem.

In this type of situation, I generally begin by ruling out everything around the drive: the cable, power supply, USB port, adapter or enclosure. This can sometimes reveal that the drive itself is still perfectly functional.

However, if the drive disappears during a transfer, disconnects once it becomes warm or is only recognised after several attempts, it should no longer be used normally.

Does a slow hard drive necessarily mean it is failing?

No. Older mechanical hard drives are naturally much slower than modern SSDs, particularly when Windows starts, several programs are opened or updates are being installed.

A computer can therefore feel extremely slow even when its drive has no physical fault. The drive may still be working correctly, but its performance may no longer be suitable for a modern operating system.

The difference can often be seen in the way the problem develops:

• an old but healthy drive is often consistently slow over a long period;
• a failing drive often shows a new, irregular or rapidly worsening slowdown;
• a failing drive may also produce errors, disappear or freeze during transfers;
• a drive that is simply full may improve after space is cleared;
• a computer with insufficient RAM may heavily use a perfectly healthy drive.

If the drive is still healthy but severely limits performance, replacing the HDD with an SSD can give the computer a new lease of life. That decision should come after checking the drive and protecting the data, rather than being treated as an automatic answer to every slow computer.

Checking the drive with CrystalDiskInfo

On Windows, I use CrystalDiskInfo as one of the tools for obtaining an initial overview of a drive’s condition. It reads the SMART information recorded by the drive.

SMART stands for Self-Monitoring, Analysis and Reporting Technology. It is a monitoring system built into hard drives and many SSDs.

Depending on the model, the available information may include:

• the number of reallocated sectors;
• sectors waiting to be reallocated;
• uncorrectable read errors;
• total operating hours;
• temperature;
• communication errors;
• the number of starts and stops.

What are reallocated sectors?

When a drive detects that an area is no longer reliable, it may stop using it and redirect the data to a spare area. This is known as sector reallocation.

A small number of values does not always allow you to predict exactly when a drive will fail. However, an increase in reallocated sectors, unstable sectors or uncorrectable errors is a serious warning sign.

A “Good” status is not a guarantee

I prefer to be clear: CrystalDiskInfo is useful, but it does not replace a complete diagnosis.

A drive may display a “Good” status and still fail shortly afterwards. Some electronic or mechanical faults occur before the SMART values have reached their warning thresholds.

Conversely, a SMART warning does not necessarily mean that the drive will stop working within the next hour. It means that the drive should no longer hold the only copy of important data.

What should you do if the drive is still accessible?

If the drive can still be read, is not making worrying mechanical noises and contains important data, the priority is not to repair Windows or immediately identify the exact fault. The priority is to create another copy of the data.

Start with the files that cannot be replaced

Do not necessarily begin by copying the entire drive in a random order. Start with the files that cannot easily be replaced:

• personal photographs and videos;
• administrative documents;
• business documents;
• accounts and bookkeeping records;
• email archives;
• work projects;
• files that exist nowhere else.

Windows, applications and most software can be reinstalled. Personal memories and certain documents cannot.

Copy the data to a different device

The data must be copied to a different physical drive, a NAS or a suitable cloud-storage service. Creating another folder on the same drive is not a backup: if the drive fails, both folders become inaccessible.

Recovered files should not be saved back onto the failing drive either. Doing so may overwrite data that could still be recoverable and places further strain on the device.

Cloning may be safer than a standard file copy

When a drive contains unreadable areas, a normal copy through File Explorer may remain stuck for a long time on one damaged file.

In some situations, I prefer to clone the drive to a healthy device before working with the files. The aim is to reduce the amount of work carried out directly on the original drive and create as complete a copy as possible.

This is not always harmless, however. Cloning can place considerable strain on the drive and is not suitable for a serious mechanical fault.

If the drive is later replaced, you will then need to decide whether to transfer the existing system or begin again with a clean installation. I explain this choice in my guide to disk cloning and clean Windows installations.

What you should not do with a suspicious drive

I regularly see situations made worse by well-intentioned attempts to fix the problem. With an unstable drive, avoid operations that write new data, unnecessarily stress the mechanics or alter the structure of the file system.

Do not keep restarting it

Restarting a drive that is clicking or struggling to spin does not repair it. It adds further start-up cycles and may worsen the damage.

Do not immediately run a file-system repair

Tools such as CHKDSK can be useful for certain logical problems, but they modify the structure of the file system. They should not automatically be run on a physically unstable drive containing important data.

Before attempting any repair, I prefer to have a usable backup or clone.

Do not format the drive because Windows asks you to

If Windows says that a drive needs to be formatted or initialised, this does not necessarily mean that it is empty.

The operating system may simply be unable to read the partition or file system correctly. Formatting or initialising the drive writes new information to it and may make recovery more difficult.

Do not install recovery software on the affected drive

If recovery software is used, it must be installed on another drive. Recovered files must also be saved somewhere else.

Installing software or downloading files onto the affected drive may overwrite deleted or damaged data that could otherwise still be recovered.

Never open the hard drive itself

Opening the metal casing of a hard drive does not allow you to reposition the read head safely in a normal room. Dust in an ordinary environment can contaminate the platters and cause permanent damage.

Opening a hard drive mechanically requires a controlled environment, specialised equipment and a data-recovery professional.

When should you stop using the drive immediately?

I recommend avoiding any unnecessary power-up when one or more of the following applies:

• the drive is clicking, grinding or producing a new mechanical noise;
• it was dropped or suffered an impact while running;
• it no longer spins normally;
• it repeatedly disappears during reading;
• it causes several computers to freeze completely;
• the data is particularly important and exists nowhere else;
• an initial copy attempt has already made the problem noticeably worse;
• the drive is not recognised despite checking the cable and enclosure.

In these situations, every additional attempt should have a clear purpose. The aim is no longer to return the drive to normal daily use, but to preserve the best possible chance of recovering the files.

I can deal with certain logical faults, carry out an initial diagnosis and work with drives that remain sufficiently accessible. For mechanical failures or recovery requiring a clean-room environment, Tera24 works with Clinique de Données, an official specialist partner.

My article about data recovery in Dordogne explains the difference between cases that can be handled locally and those that require specialist laboratory equipment.

Should you replace a drive after the first warning?

A serious warning about the condition of a drive generally justifies replacing it, especially when it contains the operating system or important data.

This does not mean that the entire computer needs to be replaced. In many PCs, the storage drive is a replaceable component. If the rest of the computer still suits your needs, installing an SSD may be a sensible and durable repair.

Before choosing the replacement, you should still check:

• the physical format and interface supported by the computer;
• the capacity you genuinely need;
• the general condition of the computer;
• whether the old drive can safely be backed up or cloned;
• whether the repair is economically worthwhile;
• whether Windows should be reinstalled.

Repairing before replacing is generally the right approach, but continuing to rely on a drive showing reliable signs of failure is not a real saving.

The biggest warning sign: having only one copy

Even a drive that appears perfectly healthy today can fail tomorrow, be damaged by a power surge, suffer a fall or be affected by malicious software.

SMART monitoring and health checks are useful, but they never replace a backup. The best protection is not predicting the exact moment a drive will fail. It is ensuring that the failure does not cause permanent data loss.

For important data, I recommend keeping at least one copy on a separate device. For irreplaceable or professional documents, a second copy stored elsewhere or with a suitable cloud service provides additional protection.

A backup must also be checked. An external drive that has been stored for years but never opened is not reliable protection until you have confirmed that the files can actually be read.

In summary: how can you recognise a failing hard drive?

A hard drive may be failing if it produces unusual mechanical noises, read errors, corrupted files, repeated disconnections, extremely slow transfers or a SMART warning.

Slowness alone is not enough to condemn the drive. The cable, enclosure, Windows installation, available storage space and other possible causes should also be checked.

When several symptoms appear together, or the drive contains the only copy of important data, the priority is straightforward: reduce its use, copy what remains accessible and avoid operations that write new data to the drive.

Software can help with an initial assessment, but it cannot predict the exact date of failure or guarantee that a drive is completely reliable.

Frequently asked questions about failing hard drives

How long can a hard drive continue working after a SMART warning?

There is no reliable way to predict this. The drive may continue working for some time or become inaccessible very quickly. A SMART warning should be treated as a reason to back up the data and arrange a replacement.

Is a noisy hard drive always dead?

A mechanical drive naturally produces a small amount of noise. Repeated clicking, grinding or continuous attempts to start are not normal, however. If the data is important, avoid restarting the drive unnecessarily.

Can CrystalDiskInfo repair a hard drive?

No. CrystalDiskInfo reads health information reported by the drive, but it cannot repair mechanical damage or physically defective sectors. It is a diagnostic tool, not a repair tool.

Can data be recovered from a hard drive that no longer starts?

That depends on the cause of the fault and the physical condition of the drive. Some logical or electronic faults may still allow recovery, while others require specialist laboratory work. Complete recovery can never be guaranteed before the drive has been diagnosed.

Can I continue using a drive marked “Caution”?

I do not recommend continuing to store important data on it. Copy anything that remains accessible to another device and replace the drive.

Does an SSD show the same signs of failure as a hard drive?

Not exactly. An SSD contains no moving parts and therefore does not produce clicking noises. It can still cause errors, freezing, slowdowns, intermittent detection or suddenly become inaccessible.