What are bad sectors? [Explanation of bad sectors in 2024]

What are bad sectors?

Hard drive failure, data loss, and data recovery are some hot phrases in this digital world. There can be numerous causes for data loss or corruption. Among various possibilities, bad sectors on the hard drive are one of the reasons behind such issues. These sectors significantly impact the likelihood of data loss.

Bad sectors occur due to mechanical damage, commonly resulting from head crashes, manufacturing defects, wear and tear, physical pressure, sudden power loss, or dust intrusion. In the context of data storage, bad sectors pose a threat to information security. Physical damage often leads to corruption in parts of multiple files.

What are bad sectors?

Due to its mechanical components, a Hard Disk Drive (HDD) is susceptible to damage. Undoubtedly, bad sectors on a hard drive are a common issue. There are millions of sectors on a HDD. A sector that cannot be read is called a bad sector. It can also be categorized into hard bad sectors and soft bad sectors. Bad sectors can result from various reasons and require different strategies for repair. Let's delve deeper into them.

• Hard Bad Sector
• Soft Bad Sector

Hard bad sectors

Storage clusters on a hard drive with physical damage are called bad sectors or physical bad sectors. This can be considered a form of physical damage.

Cause

There are many reasons why bad sectors can form. For example, they may already exist from the manufacturing process. Since a hard drive has millions of sectors, it's difficult and time-consuming to check for problem areas during production. Also, user error can lead to these faulty sectors. Dropping your hard drive, exposing it to high temperatures, or letting dust accumulate can all contribute to bad sectors.

Solutions

Unfortunately, these bad sectors cannot be repaired. This means that any damaged and lost data, including the corrupt PST file, would be stored on the bad sectors of the hard drive. It is absolutely irrecoverable. So, make sure to handle your hard drive with care.

Soft bad sector

Soft bad sectors, also known as logical bad sectors, refer to clusters on a hard drive that exhibit malfunctioning behavior. When your computer's operating system attempts to read disk data from such sectors, the Error Correction Code (ECC) may not match the sector's content. Consequently, the sector becomes unreadable.

Cause

Often, soft bad sectors are caused by software issues. For example, if you experience a sudden power outage, your computer will shut down, even if your hard drive was writing data to a sector. In this case, the sector in question might develop logical issues.

Solution

Unlike a hard bad sector, a soft bad sector can be repaired. Luckily, most computer systems come with built-in disk repair tools. Windows uses the CHKDSK utility to fix these issues. This tool is very helpful in repairing weakened or damaged sectors. In most cases, after the repair, the sector can be read from and written to without issues.

Causes of Bad Sectors on HDD/SSD

In this section, we'll discuss the causes of bad sectors so that you can take the necessary precautions to avoid them.

Basic hard drive issues like bad sectors can greatly affect data storage. It's important to know the possible causes of bad sectors so you can prevent them. Check out the list below to understand what causes bad sectors.

Overheating

Hard drives operate best between 20 and 25°C. Overheating can cause the crystal oscillator clock to change and damage internal hardware. As such, adequate cooling is necessary, and you should keep your hard drive away from sources of heat.

Excessive aging

You should know that each hard drive has an expected lifespan. If your hard drive has been in use for some time, the hardware inside might have degraded significantly, causing sectors to become damaged.

Virus/malware attack

One of the most unpleasant things that can happen to a computer user is a malware or virus attack, which can also damage the disk in your hard drive. You should have effective antivirus software and other safeguards in place to protect your data.

File system error

Bad sectors on a hard drive can be due to filesystem errors. Logical errors can occur due to a corrupted filesystem, which in turn can damage sectors on the hard drive.

Improperly shutting down your computer

Hard drives operate at high speeds, and the head is positioned over various locations on the disk to read data. If power is suddenly cut off, the head needs to realign, a process that might cause it to scratch the disk, creating bad sectors. Thus, it's important to develop the habit of shutting down properly.

Dust

The most common cause of hard drive failure is dust, which, because the read/write heads float so close to the disk, can cause bad sectors if it gets in. Dust on the circuit board can also interfere with cooling.

Though most solid-state drives (SSDs) exhibit wear from write operations that affect their health, bad sectors can and do occur on SSDs as well. The signs are familiar:

• Files and folders might be corrupted or unreadable.
• It underperforms significantly.
• It has slow read speeds for certain data types.

If the system fails to recognize the SSD, the whole system may run slower than expected or not boot at all. An SSD can also develop bad sectors. While there are no moving parts in a sector (storage unit) on an SSD (which is typically flash storage), they can still fail over time and with use. The key is when they will fail and how much data loss or corruption they might cause.

Bad Sectors on SSD/HDD? How to Check and Fix Bad Sectors

Now that we know what bad sectors are, let's learn how to check for them and fix them, if possible. There are three ways to do this.

• Run CHKDSK
• Bad Sector Repair Tool (Windows PowerShell)
• Boot into Safe Mode

1. Run CHKDSK

Launch CHKDSK from the Command Prompt. Here's how to start CHKDSK in the Windows Command Prompt: 1. In the Start menu search bar, type "Command Prompt," right-click it, and select "Run as administrator." 2. In the Command Prompt window, type `chkdsk`, then press Enter. CHKDSK will scan for drive issues and notify you if repairs are needed, but without any commands, it won't attempt to fix errors.

There are specific CHKDSK commands that can correct errors found during a CHKDSK scan. Refer to the table below:

2. Bad Sector Repair Tool (Windows PowerShell)

How to fix bad sectors on Windows 10 and 11 using PowerShell: 1. Right-click the "Start" button and select "Windows PowerShell (Admin)." 2. Click "Yes" to allow PowerShell to make changes to your device. 3. In the new window, copy and paste the following command, then press the "Enter" key:

Repair Volume C – Scan and repair offline

• Run the next command: Repair-Volume C -Scan (replace C with the drive letter you need).
• Restart Windows after it's done, and check if the error is gone.

3. Boot into Safe Mode

If the issue persists, restart your PC in Safe Mode and try the fixes again.

• Check for system errors on the disk.
• Format the hard drive and run the CHKDSK command.
• Defragment the hard drive and fix disk issues using Windows PowerShell.

Restart your computer after going through these steps. You should now be able to fix disk issues.

If the hard drive is damaged due to bad sectors, or there are many soft bad sectors on the disk that frequently hang or load data slowly, then it's impossible to fix bad sectors. Therefore, to save your data, you can back up and save your data.

If you suspect that your hard drive has bad sectors, you can always use a Disk Copy Tool to back up your data. It's a reliable professional disk cloning software that can help you copy data from one HDD or SSD to another without losing any data.

What is it?

• It aids in backing up and system migration by copying the operating system to a new hard drive as a backup.
• If you clone your hard drive to an SSD, it can help your computer run faster.
• It helps create bootable USBs, CDs, or DVDs.
• In case of system failure, it aids in creating a bootable CD, DVD, or USB.
• It offers a convenient and quick way to upgrade your hard drive.
• The simple user interface of the tool eliminates the need to deal with complex migration settings. Its specific one-click auto-migration setup ensures error-free data transfer.
• It supports sector-by-sector cloning, one-click OS migration, resizing partitions while copying disks, and creation of a WinPE bootable disk.

Conclusions

All the suggested techniques usually work great in case of logical failure with HDD or SSD. But what if your hard drive is physically damaged? You can always use various data recovery software to retrieve your data. As mentioned in the article, take good care of your HDD so that it doesn't overheat, and avoid overloading it with too much data, which can cause bad sectors and soft sectors, leading to disk corruption.

More about bad sectors

Here, we will discuss what bad sectors are, how to avoid them, and whether formatting the hard drive can fix bad sectors.

1. Does bad sectors mean hard drive failure?

A bad sector is one that performs slowly or contains damaged storage space. It can also be referred to as a corrupted sector, which is no longer accessible for reading or writing. This can be detrimental to the hard drive. Bad sectors hinder a user's ability to access data segments normally.

2. How do we avoid the bad bargain?

Bad sectors can be avoided by keeping your system cool and dust-free, and by using branded hardware. Data cables should be as short as possible, and the system should be grounded. If possible, use an Uninterruptible Power Supply (UPS).

3. Will formatting the hard drive fix bad sectors?

Formatting is one of the most reliable techniques to fix hard drive issues. For most external hard drive problems, you can get away with a quick format. However, a full format is necessary when dealing with bad sectors. A full format checks for bad sectors across the entire drive and remaps them to spare sectors, rendering them unusable.