I think this issue must have been resolved by now but I just want to add that I shoot on 16G RAW CF cards and have done so since Oct 2009 when I bought my 7D. I have not had this issue nor have I had other issues I have heard about from numerous other 7D shooters many of whom have told me that they regularly have to replace their cards. I have had the same two cards for over three years and had no problems. Plus the card reader, also made by RAW once got scooped up in my laundry and went through the whole cycle. I assumed it was ruined but tried it and it worked! That was at least two years ago and I still use it. I payed about $300USD for the two cards and the card reader at the time and I know people told me I had paid too much but all of these people have had lost files and cards that had to be replaced and I just keep shooting on mine. I think it is well worth it when your career is at stake to invest in properly priced media of the right quality. Reshoots will cost far more than a good set of cards. (I don’t recommend anyone put a card reader through the wash, as good a product as it is I still think I got super lucky with that one!)