There are some ways to recover mistakenly deleted files, but not always, and it’s essential to stop using the affected drive immediately. You should be skeptical of anyone offering guaranteed file recovery services because the truth is rarely that simple.
The importance of the first minutes
I’ve witnessed people mistakenly delete an important folder and frantically download recovery programs and tools on the affected drive. As someone who has had to recover files after such actions, I can say with a straight face that doing this is the worst thing they could’ve done in terms of recovery. If you want to recover mistakenly deleted files, you need to avoid any additional software installation, browsing, and interacting with the PC until you’ve decided on a course of action.
The reason is quite simple, actually. The file you’re trying to recover most likely wasn’t actually deleted in the moment of deletion. All that was done was a pointer to the location of that file on the storage medium was removed, and the space it occupied marked as available for other data. The file can be recovered quite easily until something else is written to the place where the deleted file used to be.
Until something else is written to the storage medium, that is. Any operating system-level logs, caches, downloads, or system updates can potentially overwrite the data of a deleted file, making it unrecoverable. That’s why it’s so important to act fast after deletion. If you had the file on a secondary storage drive, it’s probably best to physically disconnect it until you’re ready for recovery. If you mistakenly deleted the file on the main system drive, it’s probably best to shut the computer down until you’re ready to recover the file. My preferred method would be to connect the drive as a secondary drive on another computer, or boot the computer from a bootable flash drive and perform the operations there. The most important thing is to avoid interacting with the disk that had the deleted file.
How does the recovery process work?
All recovery software essentially does is look for the contents of deleted files on the storage medium, and try to parse them into a file you can use. The actual recovery process will be most successful if the time between deletion and recovery is minimal. You may get away with recovering all the contents of a file, including the name and location if the file was on a secondary drive.
It all really depends on how much interaction with the drive you had after deletion. If you just had the file open on your system’s main drive and closed it right after, the chances of full recovery are higher. If you already started interacting with the disk where the file was located, the less space that file occupied, the higher the chances of recovery are. You may find that an image you’ve deleted can be partially recovered, or a document or video you’ve deleted can be played until some point.
There’s also a possibility of the file’s contents being successfully parsed, but the name and location being lost, which will result in the recovered file having some generic name. That happens because the filename is a separate piece of information that is stored alongside the file, but isn’t a part of the file itself, and can be easily overwritten.
I also wouldn’t save the recovered file on the same drive I’m scanning for deleted files on, because that would result in immediate overwrites of some parts of the drive. I’m sure some more modern and intelligent recovery software can handle this, but I prefer saving the files to another drive to avoid having multiple files being saved at the same time interfering with the recovery process.
SSDs can be an issue
Older storage mediums like hard disks, USB drives, and memory cards will typically preserve the contents of a deleted file until the drive is full or formatted. This allows for very convenient recovery of pictures that were deleted from a camera’s memory card, even weeks after deletion. It shouldn’t come as a surprise that the same method won’t work on an SSD, and may not even work on a hard disk if it has been wiped or formatted since the last deletion.
Modern operating systems issue a TRIM command to SSDs to mark deleted files for permanent erasure, which renders them unrecoverable by standard methods. There’s also a possibility that the operating system itself will erase the file right after deletion, depending on the system and file size.
It’s not unusual for the whole process of deletion and recovery to take place within the same day, and a file deleted from an SSD on a laptop may be unrecoverable within minutes or hours after deletion. The same file on an older hard disk or camera’s memory card, however, could be successfully recovered months later. This is also a strong reminder why regular backups are important, and recovery software should be used as a last resort.
A recovery operation should be seen as a salvage operation, and there’s rarely any guarantee of success. Having an automated backup of the folders that are important to you may turn a several-hour operation into a several-minute one.