Please help . I have a canon 550D, When i put my 4gb Sd card in it . It says no card in camera . Whereas it can be read easily on the laptop . please help. Whereas i have another memory card of 16 gb it works perfectly on both the laptop and the camera. Please guide some one. I have tried formatting the card many times and have even shredded it but my 4gb Sd card gives the same error on the camera saying "No card in camera" .