SD Card] I bought a Secure Digital card, but I can not write anything on it. What can I do?
The Secure Digital cards have a switch that protects from writing. It is equivalent to the write protect switch of the old floppy disks. The card is protected when the switch is pushed to the center of the card. It must be pushed to the edge to allow writing data on the card. Be careful with that switch, it is fragile.