I'm pretty sure your u520 will reformat the card. You should copy all the cards contents on to a computer. Then format the card on the phone. Then take the card out of the phone and put the files from the computer back on it....

Does Alltel, offer re-downloading? If so then wipe out your card a re-download to your device.
I'm pretty sure Alltel wouldn't make it that easy for consumers to download on a card, and take the card to another ESN (phone).

Let me ask you this, are the mp3 files and pictures from Alltel?

If so, Alltel, is going to ensure the files are downloaded from Alltel stay formatted with the ESN and card, due to copyrights.

If the downloads were from Alltel, call customer care and ask if there's a sync website, so you can transfer your info to your new phone.

If the files and pictures are from you computer and phone camera, get a card reader, and see if the card reads, it may be a bad card.

Hopefully this will give you some kind of dir...
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