Image quality settings

Patricia

I have a Canon 60D that I have been using for about a year. I use lightroom 2 to work up my images. I also shoot in raw. Recently I changed the settings on my camera image quality and now my images won't download to my lightroom. I get a message that says "the files seem to be unsupported or damaged". I have always used lightroom 2 for my raw images. Why won't it work now? The images have CR2 behind them; this is new also. I tried setting my camera back but I really don't remember what I had it on. Now I have to use the software that came with the camera to download my raw files (and I don't like it) so I know the images are not damaged. I shoot in raw, convert to tiff and work the image up from there. My whole workflow is messed up. Please help.