401: The

The "401 Unauthorized Error" is a standard HTTP response status code that indicates that a request sent to a server cannot be completed because it lacks valid authentication credentials. A clear explanation from Daniel Irvine [original link]: There's a problem with 401 Unauthorized, the HTTP status code for authentication errors. And that’s just it: it’s for authentication, not authorization. Receiving a 401 response is the server telling you, “you aren’t authenticated–either not authenticated at all or authenticated incorrectly–but please reauthenticate and try again.” To help you out, it will always include a WWW-Authenticate header that describes how to ... 401 Unauthorized The HTTP 401 Unauthorized client error response status code indicates that a request was not successful because it lacks valid authentication credentials for the requested resource. Learn about HTTP 401 status code meaning, causes, and solutions in this comprehensive guide. How to handle 401 unauthorized errors effectively