Flash Card Data Recovery

by Rod Dunne on July 13, 2010

in Data Recovery

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This article takes a look at some of the background to flash card data recovery, the file system format flash devices use and the recovery software that can be used to recover lost data.

One of the saving graces of flash memory, and flash based devices, is that they use the FAT-32 file system format that is commonly used in hard drives and external storage devices. This explains why you can plug many flash cards into a USB port and Windows will immediately identify it as a storage device.

The real benefit of supporting FAT 32 is that flash card file recovery can be done using any recovery software that supports the format – which many do. Two popular commercial options are Remo Undelete, though there are plenty of data recovery freeware options out there to also choose from. Even the commercial tools normally provide a free scan to look for files, so you only pay for the flash card data recovery when you retrieve the documents to another device.

All file recovery software work in the same way with FAT-32 systems by reading the file allocation table (FAT) on the flash card and scanning the memory for data clusters. Deleted files will still be indexed in the FAT and their associated data clusters (how your document is stored to memory) will remain on the flash card. Emptying the recycle bin does not wipe the data clusters either as it only resets the directory attributes for deleted documents in the FAT.

Over time, flash card file recovery is made all the more difficult as wear on the memory switches occurs. Many people don’t realize that all flash memory has a set lifespan and that the memory switches will start failing eventually. For regular users, this lifespan will most likely be many years or decades away.

However, if the flash card is used for running applications or an OS (both involve extensive continuous read/writes) then the memory switches will start failing sooner. No amount of PC repairs can remedy this mechanical failure and after such a crash data recovery software will only be able to identify data clusters that use healthy memory sectors.

Lastly, Windows 2000 users should always use the eject-device wizard with flash cards as this commits/transfers any remaining data to the device. If you simply unplug manually then flash card data recovery software will fail as the data will be in limbo – probably still residing in your computer’s memory cache rather than on the flash card.

As a last resort, it is always possible to use data recovery services to salvage data from your card. Compact flash data recovery is even possible by experts if the card is damaged (by fire/water/component failure) through what is called mechanical recovery. This may involve special flash memory readers and specialized software but the volume of data it can recover will depend on the level of damage.

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