I have had a similar problem using the SD explorer. I am able to create and update the listing, and everything looks good while in SD Explorer, but when I plug the card into my 2600 it shows nothing and that xx% is used. If I format the card inthe keyboard and save one file to it, then restore the data tot he card using SD Explorer, it will show several "missing" or "bad" files. I say delete those files and then I cna read and use the card in the keyboard.

My guess is that the info file is getting corrupted somehow....but that is just a guess.

Bill