The SSO server codebase currently uses OpenID 2.0 to talk to Google's authentication service. Google has deprecated that protocol. This means that new clients will not be allowed to talk to Google's authentication services anymore over OpenID 2.0, and they will phase out the use of OpenID 2.0 completely in the coming monts. We are working on upgrading the SSO server codebase to a newer protocol. That work should be complete by the end of November 2014. In the mean time, anyone is free to use the existing Curoverse SSO server for any local Arvados installation. Instructions to do so are provided on the "API server":install-api-server.html page.
Recommendation: skip this step