Gmail IMAP OAuth2 returns 400 error code

Question

When I try to connect to the Google IMAP service using the XOAUTH2 mechanism (https://developers.google.com/google-apps/gmail/xoauth2_protocol) sometimes I get the following error response:

{"status":"400","schemes":"Bearer","scope":"https://mail.google.com/"} 

I was wondering if anyone knows what exactly this 400 status was ...

Answer 1

An error message appears when you use an expired token.