I had this happen to me (twice) before I realized that I was the problem.
Before you start to use a new memory card, you should first format the card using the format command built into the camera. (check your camera's user's manual).
Failure to do this will sometimes result in the problem you have now.
The only way I could recover the card was to put the card in a card reader connected to my computer.
Then I used the computer to delete all "files and folders" from the card.
(Note: DO NOT format the card with the computer).
Then take the card and plug it into the camera and use the camera to "format" the card.
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i just bought my ixus 700 / sd 500, canon..
with the supplied sd card, it works perfectly..
i bought a lexar sd card 512 mb... it worked perfectly last night and just a few minutes ago, after i uploaded the images to the pc and deleted the images in the card,
now it says memory card error, so i tried to insert the 32 mb supplied sd card, it still works perfect, but i dont know whats wrong with the 512 mb sd card.. anybody help...

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