I'dlike to know if it's possible to solve the problem with camera row for canon EOS 5D Mark IV, opening with version of lightroom 5 and photoshop element 12 i have the follow error Could not complete your request because the file appears to be from a camera model which is not supported by the installed version of Camera Raw. Please visit the Camera Raw help documentation for additional information
You need to convert the Canon RAW files to DNG files with the free Adobe DNG converter program. Google Adobe DNG converter and look for version 9.9. Install it and run it and point it to the folder that holds the Canon RAW files (You need to copy those file to a folder on your hard drive). Once they are converted to DNG you can import them into LR.
If you don't want to convert to DNG then your other choice is to upgrade your Photoshop Elements to version 15. It is compatible with the latest Camera Raw, which supports your camera. Photoshop Elements 12 will not support a new enough version of Camera Raw to provide support for your camera.