问题 My collague and I have a C# WPF project, which manage courses in Google Classroom. We create the project in Google API platform. We are the owner of the project. Both have OAuth 2.0 Client IDs. (but it doesn't matter) I allow all of Classroom API's scope. I am the domain admin of our Gsuite for Education. Google Classroom API is allowed in the domain. He can login and use the program, there is not any error, every function is ok. I can't, because i got an error 400, invalid_request Account