There are three reasons first the card SD or SDHC may be locked I'll include a diagram for this little nasty lock the switch needs to be pushed forward towards the top edge closest to the gold contacts. Another once you have the lock in the unlock position is that the card will need to be formatted to the camera you are going to us it in. Last you may have purchase a memory card greater in capacity then the cameras firmware will allow. For this you would need to go onto the manufacturers web site and download the most current firmware. BUT most of the time it's this little lock or you didn't format the card
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There are three reasons first the card SD or SDHC may be locked I'll include a diagram for this little nasty lock the switch needs to be pushed forward towards the top edge closest to the gold contacts.
Another once you have the lock in the unlock position is that the card will need to be formatted to the camera you are going to us it in.
Last you may have purchase a memory card greater in capacity then the cameras firmware will allow. For this you would need to go onto the manufacturers web site and download the most current firmware. BUT most of the time it's this little lock or you didn't format the card