When a file is deleted from your computer, it may seem like it’s gone forever. However, that is often not the case. Deleted files can frequently be recovered, even if they were deleted a while ago. Here’s an overview of how deleted file recovery works and when you may be able to search for and restore deleted files.
How Deleted Files Are Handled by Your Computer
When you delete a file on your computer, the operating system does not immediately wipe the data from your storage device. Instead, it marks the space occupied by the file as available for new data. The file remains intact in that space until the space is overwritten by something else.
This means there is a window of opportunity between when a file is deleted and when the space it occupied is reused. As long as the file has not been overwritten, recovery software can scan your device’s storage and search for deleted files that are still intact and restore them.
When Can You Recover Deleted Files?
How long of a window you have for recovering a deleted file depends on a few key factors:
- How full your storage device is – The fuller your storage device, the higher the chance deleted files will be quickly overwritten by new data. With more free space, it takes longer to overwrite deleted file space.
- What type of storage device you use – On traditional spinning hard disk drives, it may take weeks for deleted files to be overwritten. On solid state devices like flash drives or SSDs, overwrite happens much quicker, in hours or days.
- How actively you use and modify files – The more files you create, download, and save, the quicker deleted file space will be needed and reused.
As a general rule, your chances of recovering a deleted file are highest within the first day or two after deletion. After two weeks, it becomes unlikely you will be able to recover a deleted file, unless you are dealing with rarely modified media like an external backup hard drive.
When Is Deleted File Recovery Impossible?
While deleted files can often be recovered, there are some cases where it simply won’t be possible:
- You manually securely deleted the file – Using a wipe tool removes any chance of recovery.
- The storage space has been overwritten – Once new data writes over a deleted file, recovery is impossible.
- The storage device was reformatted – Reformatting replaces the entire file system.
- The device was physically damaged – Damaged hardware can make file recovery impossible.
- Too much time has elapsed – As time passes, the likelihood of overwrite increases.
So if you want to recover a deleted file, it’s critical to act as soon as possible and avoid anything that may overwrite the data.
How Undelete Tools Work
There are various free and paid data recovery programs that can search for and restore deleted files. They work by scanning the raw data on a storage device sector by sector looking for traces of deleted files that still reside intact on the device. Two common approaches used are:
- File carving – Searches for and extracts files based on their headers, footers, and internal structures. Useful for recovering files when a storage device’s file system is corrupted or has been formatted.
- File system parsing – Analyzes and rebuilds a device’s file system structures to find existing files marked as deleted recoverable files. More useful when trying to recover deleted files from an intact file system.
File Carving
File carving recovery tools do not rely on a storage device’s file system to find recoverable files. Instead, they look at the raw data on the device sector-by-sector. When they find recognizable patterns indicating the start and end of a file, such as headers and footers, they can carve out and reconstruct that file.
Common file types like JPEGs, PDFs, and Word documents all have identifiable structures that make carving possible. File carving has the advantage of being able to recover files even when a file system is corrupted or has been formatted.
File System Parsing
Undelete tools using file system parsing take advantage of the metadata stored in a healthy file system to identify deleted but recoverable files. In an intact file system, data about all files including deleted ones will still be present and can be analyzed to recover files.
By reading and analyzing the file system tables and structures on a drive, undelete tools can find the contents, names, locations and other metadata about deleted files. If the space a deleted file resided has not been overwritten, it can easily recover the file using this metadata.
File system parsing does not work if a file system has been corrupted or reformatted. But when successful, it easily recovers deleted files with file names, folder structures, dates, and other metadata intact.
Free Recovery Software
There are a number of free undelete and data recovery tools available to help you attempt to recover deleted files in Windows and Mac OS. Here are some of the better free options to try:
Recuva (Windows)
Recuva is a free deleted file recovery tool from Piriform that is easy to use with a wizard-based interface. It supports both file carving and file system parsing recovery on hard drives, memory cards, USB drives, and other storage devices.
TestDisk (Windows/Mac/Linux)
TestDisk is a free open source data recovery tool primarily designed for file carving. It can recover lost partitions as well as undelete files from FAT, exFAT, NTFS, ext2, ext3, ext4 file systems. It’s more complex than some tools but is very powerful.
PhotoRec (Windows/Mac/Linux)
PhotoRec is a free file carving tool designed for undeleting photos, videos, documents, and other files from hard disks, CD-ROMs, memory cards. It’s part of the same open source project as TestDisk.
Can System Restore Recover Deleted Files?
Microsoft Windows has a built-in System Restore feature that tracks changes to your system and allows you to rollback system file modifications to undo changes and restore things to a previous state. System Restore does not monitor your personal files and folders by default. But it can help recover deleted files in some cases.
If you have System Restore enabled and functioning properly in Windows, personal files that have been removed may still be present in restore points that were created before their deletion. You can browse through restore points and search for deleted files that may be available to restore.
System Restore has limitations compared to third party tools though. The search capabilities are limited and overwrite issues can still prevent file recovery. But it’s built-in and worth checking if available.
Can You Recover Deleted Files from the Recycle Bin?
When you delete files and folders on your Windows computer, they will typically go to the Recycle Bin. The Recycle Bin acts as a temporary holding place for deleted files, keeping them available for recovery until it is emptied.
If you realize you deleted a file in error, you can often easily recover it from the Recycle Bin. As long as the Recycle Bin has not been emptied, you can access it through the desktop icon or File Explorer. You can then search for your deleted files and restore them to their original location.
However, it’s important not to continue filling up the Recycle Bin, as this can force it to empty itself and permanently destroy deleted files. Also be aware that the Recycle Bin does not keep indefinitely older versions of files you may want to restore.
For best results recovering deleted files from the Recycle Bin, do so immediately after deletion and avoid letting it fill up. Also understand the Recycle Bin does have size limits before it will permanently delete files.
Can You Use Previous File Versions to Recover Deleted Files?
In Windows 10 and 11, the File History feature can automatically create periodic snapshots and backups of your files that you can use to recover older versions of files. This can be useful for recovering a deleted file if you can find a snapshot taken before the deletion.
File History by default will save copies of files in your libraries, desktop, contacts, and favorites folders every hour they are changed. You can browse through snapshots of your files organized by date and manually restore an older copy of a deleted file.
The amount of snapshots retained depends on how much space you have allocated for File History. But it will automatically delete older snapshots as space runs out. Make sure to check for and recover older deleted files as soon as possible before they get dropped from your snapshot history.
Can You Recover Permanently Deleted Files?
When you permanently delete a file on your computer, it does bypass the Recycle Bin. However, permanent deletion does not mean the file is instantly rendered unrecoverable.
As long as the storage space occupied by the permanently deleted file has not been overwritten, data recovery software can still potentially recover it. The same principles apply as recovering normally deleted files.
However, because the file has bypassed the Recycle Bin, there is increased likelihood it will be quickly overwritten. So make sure to use data recovery tools promptly if you need to restore a permanently deleted file. The longer you wait, the less likely recovery becomes.
Takeaways
- When a file is deleted, the space it occupies is marked as available, but the actual data remains until overwritten.
- Undelete tools scan storage devices and can recover deleted files if they have not been overwritten.
- Time is of the essence – overwritten data is unrecoverable.
- Recycle Bin recover has limits, use data recovery tools for best results.
- Even permanently deleted files can potentially be recovered if space is not overwritten.
Deleted files don’t have to be gone forever if you act quickly. Data recovery tools and techniques can potentially help you get back critical deleted files before they are lost for good. So next time you face an accidental or erroneous deletion, don’t panic – try some deleted file recovery techniques right away to get your data back.