I belive the 450D is an EOS Rebel and has a CF (Compact Flash) card. While you should not normallyformat a card on a computer,if it won't format anyway (double check) it won't hurt.The format that is used is FAT (File Allocation Table). If your computer has a card reader, insert the card. Go to windows explorer, find the drive the card is in, right click and select properties. It should show you the format, (or if the card is scrambled, may not see it at all. You should see used and unused spaceand the format used ( FAT, FAT 32 , etc.). Try and format in FAT from list (should be default). I just did one to make sure in an EOS 5D, and took a shot and it worked fine. If it works (card OK) reformat in camera.


JeffersonPoster





PS, I should't have to say this but make sure that you DO NOT FORMAT C!