Can anyone tell me what is the biggest memory card a Nokia E90 can work with? Can it use a Kingston 8Gb class 10 or will it damage the card? I bought a SiliconPower 4Gb one and now the card is useless. I formatted it and then the phone didn't recognize it. When I put it in the laptop I can only store files on it and can't delete them. When I try to format it displays "Unable to format. Disk is secured." I just want to know is it worth buying this one or will the same thing happen?