If your MMC (MultiMediaCard) is locked, it means that you will not be able to access the contents of the card until you unlock it. To unlock the card, you will need to use the switch or lever that is located on the side of the card. The switch or lever should be in the "unlocked" position in order for the card to be accessed. Some MMC cards may also have a password protection feature, in which case you will need to enter the correct password in order to unlock the card. Consult the documentation that came with your MMC card for more specific instructions on how to unlock it.