UNDELETED    FILES FROM    AN SD CARD

Most cameras, smartphones and other portable devices use Secure Digital (SD) cards or CompactFlash cards for data storage. As with all digital media, data deleted from SD cards can be undeleted using file recovery software. However, there are a number of factors that make recovering data from an SD card or CompactFlash card more difficult. Read on to learn more and find out how to improve your chances for a successful file recovery from a memory card.

MEMORY CARDS HAVE SMALLER CAPACITIES The basic concept behind undeleting files is that, when a file is deleted, it isn’t immediately purged from the physical media. Rather, it is removed from the file system and marked as “free space.” The data still exists on the media until it is overwritten by new data. On hard disk drives, which may have gigabytes or terabytes worth of free space, this window of opportunity is relatively large. Memory cards, on the other hand, have much smaller capacities. Compounding the problem is that we often delete photos and data on a memory card on an as needed basis. We delete a photo or video chiefly for the purpose of making room for new data. This means that the chances that a deleted photo is overwritten in the short term is much, much higher. If you delete an SD card and then fill it to capacity with new data, then this is all but an inevitability.

MEMORY CARDS ARE CORRUPTED AT A HIGHER RATE Storage media is most vulnerable when it is being mounted or dismounted. This is why most devices will have a “safely remove media” or “eject media” feature. If a card is ejected while data is being written to it, the entire card can become corrupted, making it unreadable by normal means. Making matters worse, when a corrupted memory card is detected, many devices will recommend formatting the card, which can erase some or all of the data. When SD Cards Fail, They Fail Hard Solid-state media is often touted as advantageous over hard disk drives because it lacks moving parts. This does make solid-state media more resilient on the go, but when a solid-state drive does have a physical failure, there is little that can be done to recover the data. Whereas a hard disk drive may fail gradually, allowing you one last chance to recover your data, an SD card can fail suddenly and catastrophically. Physically repairing a failed SD card or solid-state drive is also considerably more challenging.

TIPS With the above in consideration, you should follow the tips below to maximize your chances of successfully undeleting a file from an SD card: Discontinue use of an SD card immediately after you realize you inadvertently deleted a photo or file. The more you use a card, the greater your chances of overwriting the data you deleted. When recovering data, mount it using a dedicated card reader. Some cameras and printers can serve as an interface for connecting your media to your computer, but these devices may also alter the file system or format the disk if no valid file system is detected. Never write recovered files to the same physical media that you are recovering it from.

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