I have a brand new. I have a brand new Canon PowerShot SD750 camera, I have a sundisk imback 1gb

Question

I have a brand new Canon PowerShot SD750 camera, I have a sundisk imback 1gb memory card in the camera. I took a bunch of VERY IMPORTANT photos over the past two weeks and suddenly the camera says "Memory Card Error" and I have lost access to my photos and cannot take photos unless I put in another memory card. Are my photos lost for ever, or is there a way to access them?