I am coming to this thread a little late, but I just ran into an issue where my card was unreadable and found myself here seeking help. Although I was unable to locate a fix here I did find another site that offered a successful process. I followed the following instructions and it removed the damaged file that was on my SD Card and I was able to recover all that was remaining. Thanks to the OP for the tip
1. Place the 'damaged' mini sd card into the reader that came w/ the card, and mount it to pc card reader slot. I received a confirmation beep 'device detected' sound, then the message 'e:\ not accessible, the file or directory is corrupted and unreadable'. The letter of your card reader drive may vary depending on your computer
2. Open the start menu and type Run, this will open a command window where you will type CMD and click ok. This will open a DOS window.
3. In the new DOS window enter the following Chkdsk e: /r (replace 'e' with the drive letter associated with your SD Card, make sure you enter the spaces properly). Press enter and the PC will begin reading the contents of the damaged SD card (most of the android zip files located, as well there were a number of files w/ no content). After the read completed I received my SD Card 'Auto Play' pop up window and my remaining files were accessible again
4. Type exit in the DOS window and press enter to close.
I hope this helps someone as it did me. I recovered about 3gigs of work photos and my music files from a disk I thought was toast.