The old DFP API OAuth2 scope has been deprecated. Any API requests using this scope after December 31, 2016 will fail authentication. OAuth2 requests must use the current DFP API scope (https://www.googleapis.com/auth/dfp) after that time.
https://www.googleapis.com/auth/dfp
If you use a service account to authenticate instead of a refresh token, verify that the scope you use to create credentials is: https://www.googleapis.com/auth/dfp.
If you're still unsure if this affects you, you can follow the steps below anyway with no negative impact.
If you're using a different OAuth2 authentication flow, consult the documentation for your scenario and identify where the scope is being set. If you need clarification, reach out on our developer forum for additional assistance.
- Chris Seeley, DFP API Team
