directory does not exist

hi, can anyone please help l'm using a m3 ds real cartwith a 2gb micro sd card, when l put it in and switch on the ds says that the directory does not exist, lve formatted the card and reinstalled the system folder but it just says the same, all my other micro sd cards work fine, it's just this one, it used to work ok. thanks guys.

Check if pin's in card need a clean or if they are damaged ot not..It sounds like to me that its not geting through somehowThey are two sets of pins one for micro sdcard and one for your DS, check both...

better clean it, if still cant, your card is damage...
but try to use that card to other gadget. if it doesnt work scrap it