Getting this message also, also on a tab s2. Card had been working fine, is a Samsung 64gb SD card.
I was using the card to store my uv movies from flixster. I would dl to my device and use file manager to manually move the movie files to the SD card. After dl a handful of movies this way and having no issues, I noticed the flixster app had a "dl to SD card" option. Figured it would save me the hassle of moving manually.
Well, tried to dl another movie. Go to check it after its finished and all my movies were no longer available offline. Weird. So I check storage. Showing 18gb used of my SD card, so appears fine. So go to file manager. Sd card is literally blank. Doesn't even have the file paths or anything Uh oh.
Try to format, does nothing. Take it out and re put it in and am getting the error message. I do format, it spins for minute, says checking, then back to the error message. Great, thanks a lot flixster.
Any ideas for a remedy? This is what I get for not just moving files manually I guess. Some app design.