my camera is casio ex-s3, when i turn on the camera it just said system error with black background..what should i do..??!

try removing the battery then re-inserting it. Better yet, clean the contacts while it's out. Also, i don't know if that cam has internal memory, but remove the card and try starting it, then re-insert it and try again.

when the card is not inside,the camera can works, but if i insert the memory card, it can't works. Is the card broken?