Unable to open the google earth from the link planner tool

Unable  to launch the google earth from link planner tool. 

Error message: "Unable to open KML file"

This issue can be fixed by performing either step 1 or step 2:

       It looks like the file associations for KML/KMZ files aren't correct. The easiest way to fix this is to completely uninstall and reinstall Google Earth. If you don't have the installer around then you can try the following.

Or 

        You can also manually locate the .kml file on the c:\users\X\appdata\local\temp…path showed in the error and Right-click on the .kml file and then "Open with" -> "Choose default program" to Google Earth option.

Note : X in the path is your folder name and the appdata folder may be hided on your system sometimes.