XWolf said:Just format it to FAT or FAT32! on Linux, there are no hidden __ folders when linux formats - the issue is purely regarding Mac. If the card does not work on DS after Fat format then there is another issue.
And no, ext won't work!
Normal format as Fat or Fat32 didn't work. I used Panasonic SD Formatter on computer with Windows and it's working again. After format I checked card with Gparted on Debian and it showed 4 unallocated MB at the beggining(+ normal 7,6 GB fat32 partition). What does that 4 MB means?
Sorry, for my English.