Locate your camera model and required raw plugin version for CR2's here. Then determine which version of raw was supported in Photoshop Elements 8 here. Proceed to the Help menu in Editor and select About Plugin >> Camera raw... to see which version you have.
Elements 8 will not be able to display the files from your new camera. If you don't wish to update to a new version of Elements, you can convert the files to the DNG format with this free converter and you should be able to see the files.
However, your post suggests that you cannot see ANY files from your catalog because they have been disconnected. Is that the case? If so, we need more information from you. What OS are you using? What changes in your hardware have you made?