Please can anyone help??? i have a Canon 350D and i have just taken the memory card out to put a new one in and it won't accept any of them now, neither card will fit back into the slot.
If they are going in, and as mentioned, they are facing the correct way and the pins aren't bent, (if you haven't already) try formating with the camera. I have had one incidence where a card first time around said "No CF card" (Or whatever it might say. I can't recall now) no matter how many times I put it in, but after I formatted it worked like a charm.