SD Car image indicates an "?" symbol.

[Roberto Vega]

Hello,
I took more than 200 photos with a Rebel T2i using a new SD card 32GB class-10. I don't know why can't see most of then. Just an "?" symbol is displayed when I press image reproduction. I saw a few images in my laptop but the canon program displayed an X to others. I will appreciated if someone help with this.

 

[blade of grass]

Can you see them in-camera? What software are you using? Are you shooting RAW or JPEG?