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My SD card has a broken boot sector and the tools I've tried say that it's not repairable (I've tried TestDisk, DriveRestore Pro and Easeus Partition Recovery).

The card was in my Android phone and at one point, it simply shut down and I had to reboot it. After I rebooted it, the SD card was not recognized and since then I've tried to recover it (I don't want to format the card as it contains some data I'd like not to lose although it's nothing critical).

My question is, can some software error in Android, or a sudden crash of a system, damage the SD card? Or was it the other way around, the card first died and it brought the system down?

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Memory cards do have a limited number of writes ( What's the life expectancy of an SD card? ). While in most devices, like a camera, it would most likely last the life of the device due to how often you are actually writing to the card. But in Android you can do things like move the application data to the SD card, store media files, and/or downloaded files which I believe speeds up the "death" of the card. I even attempted to use

mkfs.vfat -c /dev/###

To see if I could detect the bad parts of the SD card and make it usable again. Shortly afterwards in my Android device random files with random character file names showed up.

Like you I attempted to use testdisk and was unsuccessful. I don't know what else you can try but as a lesson learned I setup Syncme ( ) and backup my Android SD card contents to my NAS. I attempted to use foldersync - but it seemed it wanted to sync my 6TB NAS onto my 32GB SD card. The only thing sycme doesn't seem to be able to backup is the applications - but that's not that big of a deal (I'm more concerned about pictures and personal data).

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I have heard of situations where a SD card that was formatted in a different operating system, would give these first sector problems, when put in a different operating system. I would have thought that they would resolved issues like this by now.

If you have access to whatever originally formatted it, try and do a diskcheck, or disk repair on that device. If you used a specific operating system to format the card, say Ubtanim(sp), then try and run check in that OS. In those situations the disk would usually format in the "other" system, they just had recognition and data problems.

Remember that there are file systems used by Android, and Linux that do not work in all Windows systems, until the Windows system has a driver for that file system.

Note about the card's physical connection points: I have never had to, but check and clean the connection points without damaging them. At the same time, check for any cracks or breakages. If an adapter is being used, or a card reader, you might have to confirm that they work normally.

Many thousands of cheap SD cards are being sold, that do not have the actual memory on them they are sold as. A part of the card is written to trick the systems into thinking that the memory is there, they will format (because an SD card does not really format) and they will partition. But when you go to slam into the REAL end of the disk, they corrupt. Then you go to try and fix it, and this trick they put in to fake the size. Well, you get the rest of the picture.

My first question when a friend asks this is: where did you buy it (eBay)? How much did you pay for it (way less than a real one would costs)? When did it die? (while putting lots of data on). Did you do a speed test, wrote to the whole thing, and then did a compare of the whole thing before starting to use it? Well, of course they did not.

Can software damage a card. Sure, if the jerks can screw up the sectors to lie, and make a self-destructing card, then so too could some software.

Is there hope? Over at a ChinaMp3 forum, where they deal with thousands of MP3 and MP4 players that are hacked to fake the memory quantity, they have managed to get the flash chips back to their real size and then have the unit usable again.

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