For further information, the Raw file format is different for every single camera model.
Accordingly, every time a new camera model is released to market, Adobe has to update the Camera Raw plugin used by Photoshop Elements so that the Raw files can be opened.
These updates are usually issued periodically to include support for whatever cameras are released by the various camera makers in a certain timeframe. Support for brand new camera models may require a waiting period of several weeks for the Camera Raw update to be released.
Check which version of Camera Raw you are currently running by clicking Photoshop Elements > About Plug-Ins > Camera Raw.