We are facing the below screen when trying to authenticate to Google. The app that we are trying to authenticate is used for internal development and we did not publish it to our users.
Any idea why this occurs?
We faced an Unverified App screen before (as below) but now the authentication is disabled.
Starting July 18, 2017, Google OAuth clients that request certain sensitive OAuth scopes will be subject to review by Google.
OAuth Client Verification Starting July 18, 2017, Google OAuth clients that request certain sensitive OAuth scopes will be subject to review by Google.
Review is not required if you are only using it under the same account as created the project in Google Developer console. You can read more about this change in this help center article.
This change applies to Google OAuth web clients, including those used by all Apps Script projects. By verifying your app with Google, you can remove the unverified app screen from your authorization flow and give your users confidence that your app is non-malicious.
Once you have applied for verification it takes around a week and it should start working.