What is Data Recovery and How it Works?



A common problem faced by users of computers and other electronic devices worldwide is losing essential data. Data loss often occurs due to physical damage to the storage devices or logical damage to the file system. Data files could suddenly become inaccessible, corrupted, damaged, lost, or sometimes accidentally deleted.

While the loss of data is a common occurrence in computer devices, recovering lost data has been made possible and easy with the use of different data recovery tools and services. Continue reading to learn all about data recovery, the chances and limitations of data recovery, and how to prevent data loss.

Part 1. Why Can Deleted Files Be Recovered?

Although not every data can be recovered once they are deleted, it is possible to recover your deleted information or lost files. Data recovery is made possible by the various operating systems of computers and electronic devices. This part focuses on what happens after your files are deleted, and reasons why your files are not erased from your system immediately after deletion.

What Happens When You Delete a File

Many people wonder why their files and data can still be located and restored even after deleting the data and emptying the reference from the recycle bins and trash. Here is what happens when you delete a file from your computer device.

When you delete a file either purposely or mistakenly from your mobile phone or computer system, it doesn’t just vanish into thin air. Instead, depending on your device operating system, the deleted file is swiftly moved to the recycle bin in windows devices or the trash in your iOS devices, pending your next line of action. You can either restore the deleted files from the trash or recycle bin or permanently delete the files by emptying the trash or recycle bin.

Even after emptying the trash, permanently deleted files don’t just vanish. The files are technically still present in your device but only not visible to you or the computer system and mobile devices. Instead, what happens is that the reference to the file is removed from the operating system directory.

This implies that while the file still exists in your device, your operating system will neither be able to recognize the location of the file nor have access to the file or data. The reason is that the file has automatically become invincible, and space formally occupied by the file will be recognized as free and can receive and new data or files.

Why Deleted Files Aren't Erased Immediately

Every operating system is built to maximize the computing speed for efficient computer system utilization and devices. For the primary purpose of speed and efficient utilization of the system, your computer devices are designed to hide instead of automatically erase your deleted files.

When you delete a file from your device, the deleted data is hidden instead of automatically erased. The deletion process takes very little time since the computer is merely deleting the file’s pointer to make its space available for other files. The main reason why files aren’t erased when you delete them is that the file’s actual deletion will take too much time, not worth it.

For example, if you are deleting a file worth ten gigs of data from your computer system, you will notice that the ten gig file gets deleted rather too quickly. That is because the file is not erased from your computer system, but only removing the reference. If the ten gig file were to be truly deleted from your computer, it would take several minutes or hours, depending on the size of data to be deleted. Simple deletion is much easier and faster for the computer than having to overwrite the data instantaneously. You will also find the process advantageous to you since you can quickly recover the deleted files if need be or erase them by overwriting the data by inputting new files into the computer system.

Part 2: How does data recovery work?

Lost data on your computer devices can be recovered with the use of data recovery services and software. The process of data recovery varies depending on the nature and extent of the problem. Data recovery can either be done with a data recovery software or a by professional data recovery service providers.

Data Recovery with software or by a service provider is possible because your device’s operating system keeps track of every data (whether deleted or not) in the system or any external drive connected to your computer through ‘pointers’ or allocation tables. These pointers can pinpoint the exact spots where your deleted files are hidden. The deleted data would be intact somewhere inaccessible to you in the storage drive, as it awaits restoration or overwritten by new data.

The pointers or allocation tables of files and data in any computer system are situated in different locations from the actual files and data. That implies that once you delete a file from your computer, only the pointers or allocation tables are hidden or made invincible to you. However, the main files or data are intact and can be accessed by a good data recovery software. Once the data recovery software successfully accesses the pointers,  the lost or deleted data can then be found.

What the data recovery software or professional data recovery service providers do is to use file signatures to scan every bit of the storage drive till it locates all the lost files in the system. The missing files, when found, can be in perfect condition, which makes them easy to retrieve. However, there are cases where the files would be seen to be damaged or encrypted.

If the files are encrypted or damaged, all hope is not yet lost as a professional data recovery software can still piece the files together and retrieve your files, leaving them in perfect condition. If the data is lost due to minor physical damage on the hard drive, your lost data can still be salvaged by a professional data recovery service provider.

Part 3: Is data recovery safe?

Yes, data recovery is very safe.  However, there are certain conditions where data recovery is not safe. If you want to avoid permanent loss or damage to your data during a data recovery process, there are specific safety measures you must abide by, and you should heed them.

Even if you are using the best data recovery software to recover your data, certain factors can still affect your data’s safety. Some of these factors include the drive’s condition, where the data is located, and the file’s state that needs to be recovered.

Likewise,  the file format that needs to be recovered, if the cause of the data loss is due to a hardware malfunction, and several other factors come into play. Before using any data recovery software or tool to recover lost files from your device, make sure you check these factors for your data’s safety.

Part 4: When to Use Data Recovery Software

If you suddenly lost your files and need to recover them ASAP, professional data recovery software is the easiest and fastest data recovery method to use. However, suppose the problem is due to a hardware malfunction. In that case, the drive is having mechanical issues, if there is an electrical fault with the hard drive, or if there is a firmware failure, a data recovery software might not help resolve the problems. In such situations, you might need data recovery software.

If you have issues identifying when to use a data recovery software to recover lost files from your device, keep reading to identify some of the cases where you can use a data recovery software to recover lost files.

Logical failures

Logical failures usually cause a system to behave unpredictably. Logical failures can cause unexpected failures and make your computer system malfunction in more than one way. Logical failures occur when you fail to access data on your hard drive after facing a non-mechanical issue with the hard drive.
Some of the common forms of logical failures in a computer device include; the damage done to the file directory by a virus or other malicious programs, involuntary deletion of files, unintentional formatting of the hard drive, overwritten data, and the corruption of the operating system. Sometimes, logical failures can resemble physical failures in terms of their traits.

If your device is experiencing logical failures, the best course of action is to use professional data recovery software. With the software, you can recover your files lost due to the system’s logical failure and fix the issues. Once you suspect a logical failure, try not to boot or use the hard drive until the issue is resolved with a professional data recovery software.

Virus attacks

Computer viruses are usually designed to damage your computer programs, delete your files and data, reformat your hard drive, or execute any other harmful or malicious actions that will disrupt your computer system’s performance and eventually cause it to crash.

When your computer system or hard drive is facing a virus attack, and you suddenly lost important files or data, the software and fastest way to recover your lost, deleted, or formatted files is with the help of a professional data recovery software.

If your computer system is exhibiting strange behaviors like slow performance, erratic behaviors, unexplained and sudden data loss, and frequently crashing, halt the computer’s operation, then download and install a professional data recovery software to retrieve your lost data. The data recovery software can help you recover or retrieve every lost or formatted data from your computer system.

Accidental deletion

It is prevalent for computer files to get deleted during use accidentally. The files can be either permanently deleted from your computer or emptied from the recycle bin or trash. Your files can also accidentally get deleted when your system starts malfunctioning or failing. Either way, it is still possible to restore such files.

If you accidentally deleted any important files from your computer device and you need to recover them promptly, you can use professional data recovery software to help you retrieve your lost data or files.

Immediately you notice that some of your important files have been accidentally deleted, stop using the affected computer system or hard drive to avoid overwriting the file with new data, and get a professional data recovery software to recover the accidentally deleted files from your computer system quickly.

Disk formatting

Disk formatting is a prevalent cause of data loss on computer systems.  Disk formatting occurs due to different reasons. Some of these reasons are: the computer system may be facing some firmware issues which will force you to format the disk. And you may be experiencing a hard disk crash, or your hard disk can get formatted due to an unstable power supply. Likewise, you may be facing some mechanical or internal failures, and your files might have gotten corrupted, or you accidentally formatted the hard disk.

If you face any of these issues, do not save any more files on the formatted hard disk to avoid overwriting. Download and install a professional data recovery software to retrieve your lost data. The best professional data recovery software currently available is Wondershare Recoverit Data Recovery. It’s fast, efficient, and easy to use.

Part 5: File System Type and Data Recovery Chances

Due to professional data recovery software availability, data recovery is becoming increasingly popular and very easy to achieve. Data loss occurs for various reasons, such as virus attacks, system formatting, and logical failures.

File systems usually oversee the allocation of data on your computer system. It also regulates how data is stored and manipulated on the storage medium. Generally, the file system manages the data on a computer. It decides how any data is handled during and after deleting the file. That implies that the chances of data recovery depend entirely on the file system type.

Keep reading to learn all about file system types on Windows and Mac OS and the data recovery chances with each file system. The chances of data recovery will be reviewed based on the file system structure and how they behave during formatting and deletion.

Windows File Systems

The windows file systems reviewed here are the NTFS file system, FAT/FAT32 file system, and the exFAT file system.
  • NTFS File System

NTFS usually uses the Master File Table (MFT) to coordinate files. The table contains every detail about the files and folders in the system, including each file’s name, its size, time and date of creation, and modification details.

File Deletion

The NTFS file system does not erase deleted files from the computer system. Instead, it will only delete the file entry from the directory and translate the file record in the MFT as ‘unused,’ thereby making the file location available.

If the data is not overwritten and its record remains unchanged, there is a 100% chance of data recovery since every detail is still available in the MFT. If the file record is deleted, data recovery is still possible if you use the RAW recovery method to recover the lost files by bypassing the file system structure.

File Formatting

During file formatting, the MTF tail is left untouched while the beginning is wiped and it’s record lost. This makes the ending parts of the file available for restoration if need be.

Recovering the last 256 files (tail end) of the formatted data has a 100% chance of data recovery success. However, if you need the first 256 files from the computer system, you will need to use the RAW-recovery method to retrieve the files.

  • FAT/FAT32 File System

The FAT/FAT32 file system uses the File Allocation Table (FAT) in coordinating system files. The table contains an entry for the filegroups on the disk. It also creates a link to connect each file group to the file’s location on the disk. The FAT file system does not apply the method of defragmenting any fragmented files.

The FAT also contains the links to the file start, its continuation, and the end. The FAT file usually possesses eight symbols for the file name, and 3 for the file extension, making it possible to store long file names and using the long file extension feature.

File Deletion and Formatting

The file system deletes every information concerning the removed files from the start to the end in the FAT file system. However, the data area is not cleared or erased but only deletes the first symbol of the file name. In the case of the FAT 32 file system, every piece of information about the first part of the filegroups is deleted.

During data recovery, information on the file start can be found in the system while information concerning the continuation and the end of the files remains cleared. This makes data recovery chance very difficult since it doesn’t use the method of defragmenting files. There is, however, a little chance to recover the deleted or formatted files using the RAW-recovery method. Long names will most likely not be recovered.

  • exFAT File System

The exFAT file system also uses the FAT in coordinating files. Which holds and connects the link for each file group to the file location on the disk. The FAT contains the link to the file start, continuation, and end.

The FAT contains the entry for each filegroup and also provides a link from the FAT to the location of the file on the disk. The links provided are links to the file start, continuation, and end. Mostly, the exFAT file system does not fragment files; neither does it link to the sub-directories of the file.

File Deletion and Formatting

During file deletion and formatting, the information of the files in the File Allocation Table is deleted, and the file continuation and the end links are also deleted. However, the primary data in the file location is not erased from the file system.

Since the links to the file continuation and end are lost during formatting or deletion, recovering these files may be incomplete. Due to the low rate of file fragmentation in the file system, the chances of recovering lost files from the computer system is very when using the RAW-recovery method.

Mac OS File Systems

The Mac OS file system types reviewed here are the HFS+ file system and the APFS file system.
  • HFS+ File System

The HFS+ file system support uses journaling to track file system modifications. Since the journal is limited in size, the file system overwrites older information to modify new changes. The file system applies file defragmentation in its process.

The HFS+ supports hard links that are cataloged as different files in a hidden root directory that stores the information about each file.

File Deletion

During file deletion, the file system will delete the file’s hard to link from its directory, while it maintains the file’s information in the journal records for a while.

When recovering the deleted files, it is possible to use the journal records to locate an older file system state, to retrieve the hard link. Deleted file links can be replaced from the file system journal depending on how long the system was used after deletion.

Chances of recovering data from the HFS+ file system are higher if the affected computer is not used too often, as overwritten files can not be recovered. For files that are not fragmented, RAW-recovery is an excellent option for recovering deleted files once they are deleted from the journal entry.

File Formatting

During file formatting, the hard links are deleted from the file system’s directory and leave the information in the journal record untouched. The on-disc data area is also left unchanged.

Formatted files can be recovered from the HFS+ file system by addressing the file system journal. The RAW-recovery method retrieves every formatted file from the journal. Due to the hard links being deleted, the chances for recovering fragmented files are low.

  • APFS File System

The APFS file system uses a two-three method of deletion. While one tree contains the data, the order is a virtual version of the first. When data is deleted, the first tree is wiped, leaving the second tree untouched.

During data recovery, the lost data can be recovered with the second tree’s help and previous versions. However, if the second tree was also deleted, there is no chance of recovering the data.

Part 6: Scope and limitations of Data Recovery

With the aid of advanced technologies, deleted and lost data can now be recovered using a professional data recovery software or service. While lost files can be recovered quickly in most situations, there are a few conditions where data recovery is practically impossible or very difficult to achieve.

Also, while data can be recovered from almost any computer or electronic device in the market, specific hard drives make it impossible to retrieve lost data. For devices with the TRIM command enabled, data recovery won’t be possible since the files are permanently deleted.

Below are some of the situations where data recovery is either difficult or not possible.

  • Situations where the data has been overwritten

When the data of any file is overwritten after its deletion or formatting, or any other cause of data loss, such file will be permanently erased from the computer system. This makes it impossible to recover an overwritten file with data recovery software or any other data recovery method.

  • Corrupt data

When the data you intend to recover has been corrupted, the chances of retrieving such data is very low since it is challenging to recover corrupted files from the computer system. There is, however, a little chance of recovering the lost data with the use of advanced data recovery software. 

  • Failing hard drive

Recovering lost files from a hard drive that is already failing is very difficult and risky. This is because there is a high chance of overwriting or erasing the lost data in the process of data recovery, which will cause you to lose the files you were trying to retrieve permanently. Data recovery is precarious when the lost file is located in a bad sector of the failing drive.

Part 7: How to prevent loss of data?

Although data recovery is possible in most situations, there are cases where lost data are permanently erased. Luckily, there are several ways to prevent data loss to avoid the devastating effects and frustration. Follow these simple tips to prevent your data from being lost.
  • Always Create A Backup For Your Data

Each time you create or save a new file on your computer or mobile device, ensure you create a backup plan for the said file. Back up your files regularly to easily access them if need be. You should also diversify your backup by creating two or more backup plans on the cloud and your hard drive. You should also keep a copy of important files on an external hard drive for easy accessibility if you lose the original data.

  • Use Firewalls And Anti-malware Software.

The easiest way to avoid cyber criminals and hinder them from getting to your files is by using advanced firewalls and anti-malware software on your computer systems. These firewalls and software are programmed to prevent unwanted parties from intruding or harming your files and data.

  • Encrypt Sensitive Data. 

If you have sensitive data that needs protection from the public, ensure that you encrypt such data to make it impossible for thieves to decipher. Password protection of your files will ensure that no one will access and harm your files or data without permission.


  • Ensure Secure Access To Computers And Mobile Devices. 

Avoid keeping your devices in places that can be easily accessible to everyone. Physical access to your device by anyone can lead to accidental deletion of important files or the device’s theft. Also, put adequate security measures on your devices to avoid unwanted access.

  • Use a UPS on your computer system.

To avoid data failures that occur due to abrupt power failure or unstable power supply, ensure that you use a UPS when operating your computer devices. This way, even in the case of power failure, you will have the needed time to shut down the computer system properly.

  • Avoid indiscriminate deletion of computer files.

To prevent the loss of essential files from your computer system due to accidental deletion, make sure that you cross-check every file before deleting them. Also, ensure that you go through every file in your recycle bin or trash before emptying it.

The Bottom Line

Every computer user should have adequate knowledge of data recovery and how it works. This knowledge would enable you to take the appropriate course of action in the event of a data loss.

Protecting your files from data loss by taking the various preventive measures possible is the best thing to do. However, despite the preventive measures put in place, any computer user can still experience data loss due to unforeseen circumstances. In such situations, you should ensure that you employ the use of a professional data recovery tool in retrieving your data, which will ensure that your data is safe.

Remember the adage that ‘it’s better to be safe than sorry.’ That applies to your computers too, so do your best to protect your files, but if it comes to it and you lose them and need to recover them, a data recovery software is the best solution at your disposal.

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