When want use private data in your application you need to request user authorization in order to access it. This is done though Googles Authorization server, in order to use Google’s authorization server you need to register your application on Google developer console. In order for this to work there are some things that need to be configured and when you configure them incorrectly you will
get an error.
I have a quick video which recreates the error using the Google Drive api and then shows you exactly how to fix it