Please follow the steps below to update the card firmware.
1. extract ex4ds_141_fix.nds to your root folder of TF card
2. run ex4ds_141_fix.nds on your NDS, NDSL or NDSi which version should be below 1.4.1 or 1.4.2C
3. Wait for firmware verification then press L + Start to update your card.
4. Do NOT power off or restart your DS while updating.