Skip to content

Unauthorized Client

URI: https://docs.ankatech.co/errors/unauthorized_client
HTTP Status: 401 Unauthorized

This error also corresponds to the RFC 6749 OAuth 2.0 error code unauthorized_client of the same name. The RFC 7807 type suffix uses the identical underscore form so the two identifiers match.

When you see this

The authenticated client is not authorized to use the requested grant type or to perform this token request.

Common Causes

  • A client requesting a grant type it is not permitted to use.
  • A client not authorized for the requested operation.
  • A client configuration that excludes the attempted flow.

Response Example

{
  "type": "https://docs.ankatech.co/errors/unauthorized_client",
  "title": "Unauthorized Client",
  "status": 401,
  "detail": "The client is not authorized to use the requested grant type.",
  "instance": "/oauth/token",
  "correlationId": "550e8400-e29b-41d4-a716-446655440000",
  "timestamp": 1730000000
}

Content-Type: application/problem+json — the response follows RFC 7807 Problem Details.

How to Resolve

  1. Confirm which grant types the client is permitted to use.
  2. Request a grant type the client is authorized for.
  3. Update the client's authorization with an administrator if the grant type should be allowed.

For full schema definitions, examples, and interactive testing, see the Developer Hub Reference.