2.2.4.2 server_error

As defined in [RFC6749] section 4.1, after successfully retrieving an authorization grant, the OAuth 2.0 client subsequently requests an access token from the authorization server's token endpoint by including the authorization code received in the previous step. [RFC6749] section 5.2 (Error Response) defines the Error Response returned by the authorization server, if it encountered an error while processing the access token request.

In addition to the error codes defined in [RFC6749] section 5.2 (Error Response), the OAuth 2.0 Protocol Extensions define the server_error error code. Note that this error code is already defined in [RFC6749] section 4.1.2.1 as an error code returned by the authorization server when processing an authorization code grant request. The OAuth 2.0 Protocol Extensions define the same error code as a possible error code returned by the authorization server when processing an access token request. According to the requirement outlined in [RFC6749] section 6, this error code can also be returned by the authorization server if it encountered an error while processing a request to refresh an access token.