daltonracing: what year, make and model of camera? What is the maximum GB SD card is the camera rated for? (this should show in the camera manual). Going over size, the camera will not read it. If you have viewed the SD card in a digital device (not a card reader) then reinstalled it in the camera, this could be a problem. The SD card should be formatted in a computer or if the camera has this option, do it in the camera (Bushnell has this option as an example). Try a different brand of SD card. I have had good success with the following SD card brands: SanDisk, Verbatim, Lexar and Adapta. Check your batteries with a digital meter. If any one battery drops down to 1.0 to 1.2 volt, the camera will not function properly, or not at all. Even brand new batteries, fresh out of the package may have a faulty one. Best of luck.