ummm, unless i am not reading this page correctly BlackBerry - Curve Battery Life, Memory and More Specifications RIM doesn't actually say that the 8300 supports expandable memory, ergo, i am curious as to where you are installing said SD card... however, supposing that someone somewhere made a input error and your device actually supports expandable memory, then are you positive that you have it installed correctly? also, there is a limit to the size (capacity) of the SD card that a given OS will support, so, is it possible that you are trying to use a card that is simply too large (capacity) for your device?????