Mine worked fine for a while, too. I'm not sure what triggered it, but I think the phone did something to it. The reason I think this is simple. I have had many devices with SD cards in them, and never have I had one go bad. This phone was using a card that I had used for months before in another phone, and within a month the card was bad. When I looked online, I found hundreds of cases of the same issue, mostly with Samsung S3 and GN2 phones. It seems too much to be a coincidence.
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