google service account - some users not having access even when we have permission for the whole domain

Question

We are having domain level permissions for a customer and are using service account for getting access tokens. This is working alright for all users except one and we get access_denied error.

I am trying to access imap api.

Also, what does access_denied error mean? Is there a document that describes each oauth2 error on detail?

Answer 1

You can get access_denied error for a subset of users if the domain administrator turns off your app for an Organizational Unit (OU) containing the users.

See https://support.google.com/a/answer/182537?hl=en