Published in Networking.
The 401 status code, or an Unauthorized error, means that the user trying to access the resource has not been authenticated or has not been authenticated correctly. This means that the user must provide credentials to be able to view the protected resource.
An example scenario where a 401 Unauthorized error would be returned is if a user tries to access a resource that is protected by HTTP authentication, as in this Nginx tutorial. In this case, the user will receive a 401 response code until they provide a valid username and password (one that exists in the
.htpasswd file) to the web server.