I purchased a 4GB memory card for my Canon Powershot A540 ( about 5 yrs old) and it always comes up with Memory card error - card locked! even if I slide the white switch.
I have used a 1GB card with no problems since I bought the camera.
I can't format the card it seems.
Can you use the card in another device? Can you access the card un a USB card reader? If so, it is possible that the camera cannot handle a card that big. You would need to check the manual to see that it can handle a 4Gb card.
during a recent trip, the camera would take shots when i am pressing the left cursor button instead...
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during a recent trip, the camera would take shots when i am pressing the left cursor button instead of the big silver one on top, especially immediately after pressing the play mode button. Any similiar issues out there? any fixes? happens inconsistently but it does happen from time to time.