Gmail API returns 403 error code and “Delegation denied for ”

Question

Gmail API fails for one domain when retrieving messages with this error:

com.google.api.client.googleapis.json.GoogleJsonResponseException: 403 OK
{
  \"code         


        

Answer 1

Seems like best thing to do is to just always have userId="me" in your requests. That tells the API to just use the authenticated user's mailbox--no need to rely on email addresses.