If the card can be formatted, then look at page 43 of http://www.olympusamerica.com/files/oima_cckb/FE-4030_Instruction_Manual_EN.pdf
Format the card. If that doesn't clear it up, try another card. If another card fails, the camera is likely dead.
I have a memory card inserted that has plenty of space but the camera's message is "Memory full". How do I switch from internal memory to card?

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