What model of Canon are you using?
Which version of Elements are you trying to open your RAW files in?
Which version of RAW converter?
Because if you camera was made after the RAW converter software was written it will not be compatible, you need to update the RAW converter to the latest version (8.1) then your RAW files should open in Elements.
A new Canon 700D and Elements 11 I have tried Help>> Updates but no update screen appears and Help>> about Plug in >> camera RAW and am on Version 5 I see that i need update but as i say no update screen appears
Just checked your camera model and you need at least Version 7.4 of Camera Raw, Elements will probably tell you that you are up to date and not give you the option to download anything, you can get the update here