Try this. (taken from GeraldKo's guide) --- 2. [Optional] Formatting the card A. In most instances this step is unnecessary; so, at least if you don't have a card reader or Windows, skip it and see if the process turns out OK anyway. B. Download and install the Panasonic SD Memory Card Formatting Software into your Windows computer. C. Place your SD Card in a card reader. D. Use the Panasonic formatter to format the card. Select the options for FULL Erase ON and for Format Size Adjustment OFF. (It doesn't matter if the formatter reports that it can't use the Erase function.) This low-level formatting takes about 10 minutes. ---- Addon: What I discovered (and what would hopefully be useful for you), is that you can use your NIT as an SD (or if you have an n8x00 series) an SDHC reader. Just plug it into your computer, and then using the Panasonic formater, select the drive that is the SD card slot and then try formating it from there. Hope it works.