That's not a question, but I'll answer it anyway: CHA indicates a card write error. The camera doesn't think it can write to the card. If it happens with a single card, generally the card has a problem (bad sectors, improper formatting, etc.). Perform a proper low level format of the card using your computer, then reformat the card in the camera and see if that fixes the problem. If not, the card should be returned to the maker for repair. But if it happens with multiple cards, then you have to look at the camera. Take a close look inside the camera's card slot (with the card removed, obviously). If you see any bent pins or additional material in there, that would explain your problem. Unfortunately, that would also mean the camera has to go back to Nikon for repair. SecureDigital cards don't have "pins" so it's difficult to damage a camera's card slot if it uses SD. But it is still possible to damage an SD card slot.