I have an SD card which have been used in a photo camera for some months, and it's been working perfectly fine until today. It failed when we were just browsing pictures in the camera screen (so it wasn't during a file write, it was just reading photos). One of the times we switched to the next photo, it didn't show up, showing an invalid card error message instead. I then tried it in a different camera, and got a similar error message.
So I tried to read it in a Windows PC, and since it couldn't recognize the card either, it offered to format the card. I of course declined this and tried GetDataBack for FAT, which couldn't recover anything at all and returned tons of read errors.
Then I tried ZAR (Zero Assumption Recovery), a recovery tool available here: http://www.z-a-recovery.com/download.htm
It took a very long time and then it just marked ALL sectors in my card as "bad sectors" (in a grid that represents the SD card sectors, all of them were red), without recovering anything.
I find it quite surprising that a perfectly good SD card can go from 100% good to 100% bad. I can understand some sectors eventually going bad but, all of them at once? The card wasn't mistreated or shocked, so I can't see how this could happen.
So, any chance I can recover the pictures in that SD card? I'm guessing not, but who knows.