I have a 350D, 1D2 and a bunch of CF cards. The 1D2 works with all the cards (unsurprisingly). The 350D works with a 512mb standard sandisk, 2gb sandisk ultra 2 and 16mb Canon. When trying to use a 1gb Sandisk Extreeeeme the 350D complains about a "CF Error". Can't format the card or anything. As I said, the Extreeeeeeeeeme card works in several card readers and the 1D2. So anyone got any idea why the 350D doesn't like the card?