HTTP HTTP Status Codes 404 Not Found
Example
HTTP 404 Not Found means that the server couldn't find the path using the URI that the client requested.
HTTP/1.1 404 Not Found
Most often, the requested file was deleted, but sometimes it can be a document root misconfiguration or a lack of permissions (though missing permissions more frequently triggers HTTP 403 Forbidden).
For example, Microsoft's IIS writes 404.0 (0 is the sub-status) to its log files when the requested file was deleted. But when the incoming request is blocked by request filtering rules, it writes 404.5-404.19 to log files according to which rule blocks the request. A more detailed error code reference can be found at Microsoft Support.
