Is your hard drive not detected?

When a drive is not recognized due to defective areas on the unit, you should proceed with a data recovery software:

  • If it is the drive hosting the operating system concerned, cautiously disconnect it and plug it into another PC in order to proceed recovery in a secured manner.
  • If it is the memory card of a smartphone or a tablet concerned, the best option is to purchase an adapter and to plug it in a PC.

The different types of hard drive failure.

Sometimes our storage devices, hard drives or memory cards are not recognized by the operating system, making it impossible to access our professional or personal data. Here is some essential advice about what to do when a drive is not recognized.

For traditional electromagnetic hard drives, many types of failures can occur. First and foremost, the defective areas of the hard drive, linked to usage or shock, lead to the slowdown and errors, causing missing files/folders.

When the damaged areas are found in the hard drive's file system, you will be prompted to format the partition, which you should not do in order to increase the chances of retrieving data.

If the hard drive is not at all recognized by the system nor the BIOS, be sure to check that the drive is also not making any noises. Click, whirring, or scratching sounds are a sure sign of physical failure which may be causing the drive not to be recognized by your system. Also, check also that the connectors are correctly plugged in. The intervention of a data recovery engineer will be necessary to solve the problem.

Regarding external hard drives...

Today’s external hard drives assume the functions of a USB drive, but with a larger dimension and more significant storage capacity.

The transportation of large data is therefore made easier, but the consequence of this advantage is a reduced resistance to various hazards.

Internal hard drives are more susceptible to data loss, including recognition failure following physical shock, exposure to high heat, or simply a non-secured withdrawal. In all the cases, the procedure of data recovery for the external drive is the same as for an internal drive or a USB stick.

My hard drive can't be accessed but is recognized by BIOS 

If your hard drive is spinning without a problem but is not recognized by your computer's BIOs this an be a sign of logical failure. This type of failure can be the result of defective media or data corruption from another source. In this case, first check the jumpers, which will vary according to the configuration of the hard drive. You should also check that the connectors and power supply are properly connected. In severe cases, there may be a problem with the circuit board. In the majority of logical failures, you should be able to recover the data via a data recovery software.

My hard drive is not recognized and appears dead 

A burnt circuit board (PCB) is one of the most common problems seen in hard drives. A power surge, overheating or an inadequate power supply can result in a hard drive frying its spindle driver chip leaving the data inaccessible. 

In some older models, you may be able to swap the PCB from another model. But most modern hard drives have logic boards that have been adapted to the head disk it was manufactured with. In those cases, a data recovery specialist will need to rebuild the parameters or transfer them from the fried board to the donor PCB to make it fully compatible with the damaged hard drive. 

My hard drive is not being detected by Windows 

One of the most common questions we hear is, 'Microsoft Windows on my PC is not recognising my hard drive. What should I do?'

Firstly, you should restart your computer, check the connections and plug your external hard drive into another PC. If the problem persists, there could be two reasons: 

The disk is still not recognized by Windows – If you have checked the connections and plugged your hard drive into another PC, but it is still not recognized, the hard drive could be defective. 

The hard drive does not appear in Windows Explorer 10, 7 or 8 but is detected by the computer – there could be a letter assignment problem in Disk Management – the hard drive doesn't have a letter by its name, so Windows File Explorer won't be able to detect the disk partition. To assign a drive letter to it, follow these steps: 

  • Right-click on the workstation icon on your desktop 
  • Click on 'Manage' and then on 'Disk Management' in the Computer Management window
  • Select 'change drive letter and paths' 
  • In this window, click on 'Add' to assign a drive letter to hard drive partition or click 'change' to change the drive letter. 

My hard drive is not being detected on my Mac 

In this case, you should first check whether your external hard drive is recognized by another system. If you have access to a Windows or Linux PC, plug your external hard drive in; if it is recognized, perform a repair from the terminal, you can do this with the commands' diskutil list' and 'diskutil info disk'. Improper removal of the device can cause damage, so ensure you safely remove the drive before unplugging the external hard drive. 

If the external hard drive is not recognized when you plug it back into the Mac, first ensure your USB cable enables the USB port's auto-power function. If the hard drive is still not recognized, verify that the 'Finder' settings allow you to view newly connected devices. If your hard drive is NTFS formatted, non-native to the Mac, the Read Utility may need to be reset (Paragon NTFS us available in most versions of the Mac OS). If the external hard drive continues not to be readable and is not visible on the BIOS of other systems (Windows or Linux), then a hardware failure should be considered.

SSD drives, USB sticks, and memory cards: what you need to know.

The differences between mechanical hard drives and SSD drives, USB sticks, and memory cards are based on flash memory.

The non-recognition could be due to poor state of the connectors. By cleaning it with the help of a cotton swab lightly dipped in alcohol, then letting it dry thoroughly, it may be possible to solve the problem.

Alternatively, it is possible that access becomes difficult, or even impossible. This is often linked to a failure in the storage unit clusters. If the SSD drive, the stick or the card is new, this could be an original defect covered by warranty. In other cases, it could be due to excessive usage and wear & tear. It is important to know that flash memory units have several writing/suppression cycles limited for each cluster, going from 1,000 to over 100,000 depending on the quality of the product. When this limit is reached, access is more difficult and it becomes a pressing matter to consider saving the data. If the drive becomes totally inaccessible,  professional data recovery is necessary.

SSD Drives, USB Sticks, Memory Cards

My SSD / USB drive / memory card is unrecognized. What should I do? 

Unlike mechanical hard drives, SSDs, USB drives and memory cards use flash memory. If your media device is unrecognized, it may be because of the condition of the connectors. You should start by cleaning the connectors with a cotton swab moistened with alcohol to see if this solves the problem. If your device is still not recognized, it could be due to wear. Flash memory units have a limited number of write/delete cycles for each storage unit cluster, ranging from 1000 to 100,000 depending on the quality of the product. Once the limit is reached, access to the device can be limited, and if a backup has not already been put in place, one should be. If the drives become inaccessible, recovery will be required. 

Below are some of the most frequent questions we are asked regarding unrecognized hard drives. 

Why is my external hard drive not recognized by my MAC?

It could be as simple as the USB cable being worn out or that the utility of the Mac is misconfigured and is not displaying any connected devices. If the hard drive is not partitioned in HFS+ format, the Mac OS X format, or ExFat format, verify that your utility is correctly installed. 

If you have checked all of the above, there could be a hardware problem. In this case, you will need to contact a data recovery specialist. 

How to access an unrecognized hard drive?

It may seem simple but change the USB port and check that your USB cable is functioning properly. If the hard drive is appearing in the utility but is not accessible, you will need to repair it using the terminal commands. If the hard drive continues not to be recognized, you may have to use a data recovery software to locate the files. 

Is updating drivers a solution?

When your hard drive is detected by your computer but is not displayed in Windows Explorer, you can try to update the driver. To do this, you should follow these instructions: 

  1. Open the "Device Manager".
  2. Right-click on the start button then click on "device manager". In this list, a coloured indicator may appear to indicate any errors.
  3. In the "Disk drive" section, you will find the reference of your disk. Right-click on it then click on "Update Driver". The update will automatically be taken over by Windows Update. 

Should I format my hard drive?

You should only format your drive if you have no data (or data you do not need) residing on it. You will need to choose the right format that suits your computer. Opt for NTFS or FAT32 if you are on Windows, and HFS +, ExFat or Mac OS Extended if on Mac. 

Remember that formatting a hard drive will erase all the stored data, so only choose this method if your hard drive is empty. 

Facing a non-recognizable hard drive: every challenge has a solution.

When a drive is not recognized due to defective areas on the unit, you can proceed with software recovery.

If it is the drive hosting the operating system concerned, cautiously disconnect it and plug it into another PC in order to proceed recovery in a secured manner. If it is the memory card of a smartphone or a tablet concerned, the best option is to purchase an adapter and to plug it in a PC.

Free tools like TestDisk  are very effective and offers many tools to recover your files in a non-recognized hard drive. It still requires IT expertise due to its challenging interface. To benefit from an interface that is more intuitive and having the expertise of specialists, our Ontrack EasyRecovery software is an excellent choice.

In the most serious cases, such as following strong physical shock, water immersion or high heat, or if it is a drive that cannot be recognized at all, a professional data recovery in a clean room, will be necessary to save all documents, images, etc.

In all cases, in cases of doubt, it is worth seeking professional advice by specialists to avoid risking losing your data indefinitely.


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