Is your hard drive not being recognised?

  • When a drive is not recognised due to defective areas on the unit, you can proceed with a software recovery.
  • If it is the internal drive hosting the operating system, safely power down the machine, carefully disconnect the drive and plug it into another PC in order to proceed with the recovery in a secure manner.
  • If your device is a memory card for a smartphone, tablet or camera, the best option is to purchase an adaptor and to plug it in a PC.

The different types of hard drive failure

Sometimes our storage devices like hard drives or memory cards are not recognised 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 recognised.

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 physical damage, can cause errors and 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 recognised by the system, nor the BIOS, be sure to check that the drive is also not making any noises. Clicking, whirring, or scratching sounds are a sure sign of physical failure, which may be causing the drive not to be recognised by your system. In these cases, a professional data recovery engineer is required to recover the data.


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

Unlike mechanical hard drives, SSDs, USB sticks and memory cards are based on flash memory and have no moving parts.

A flash device may not be recognised by the system due to dirty or defective connectors. Carefully cleaning them with the help of a cotton wool bud, lightly dipped in alcohol, then letting it dry thoroughly, may 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, USB or memory card is new, this could be a defect covered by warranty. In other cases, it could be due to excessive usage or wear and 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 elsewhere. If the drive becomes totally inaccessible, professional data recovery is necessary.

SSDs, USB sticks and memory cards

External hard drives

Today’s external hard drives assume the function of a USB drive, but with a larger dimension and more significant storage capacity. The transportation of large quantities of data is therefore made easier, but the consequence of this advantage is a reduced resistance to various hazards.

External hard drives are more susceptible to data loss, including component failure following physical damage, exposure to high heat, or from not safely disconnecting it from a computer.


Unrecognised external hard drives for Mac

While it is often known for its superior reliability, MacOS sometimes cannot recognise an external hard drive. First of all, it is essential to check if the cable is functioning correctly. Also, there could potentially be an issue with the USB port, so it is best to try another port first. If the drive is detected, but not accessible, attempt to repair the file allocation table using the system’s disk utility.

It is enough to click on 'repair disk' to try to retrieve the data. If the operation fails, a dialogue box will pop up to notify you. If the file systems are not recognised, which sometimes occurs with the older versions of MacOS, do not format the drive, as you risk losing your data.


What to do when your hard drive isn't recognised

There are many different software solutions on the market for DIY data recovery. For an easy to use, trusted solution, we'd recommended downloading the free trial of our Ontrack EasyRecovery software to try and retrieve your lost files.

In the most serious cases, such as physical damage, water or fire damage, or when a drive cannot be recognised at all, professional data recovery in a cleanroom will be necessary to save the data.

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


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