Sun Java System Web Server 7.0 Update 4 NSAPI Developer's Guide

HTTP Protocol Version, Status Code, and Reason Phrase

The server sends back a status code, which is a three-digit numeric code. The five categories of status codes are:

Table A–1 Common HTTP Status Codes

Status Code



The Request has succeeded for the method used (GET, POST, HEAD).


The request has resulted in the creation of a new resource reference by the returned URI. 


The server has sent a response to byte range requests. 


Found. Redirection to a new URL. The original URL has moved. This result is not an error. Most browsers will get the new page. 


Use a local copy. If a browser already has a page in its cache, and the page is requested again, some browsers such as Netscape Navigator relay to the web server the “last-modified” timestamp on the browser’s cached copy. If the copy on the server is not newer than the browser’s copy, the server returns a 304 code instead of returning the page, reducing unnecessary network traffic. This result is not an error. 


Sent if the request is not a valid HTTP/1.0 or HTTP/1.1 request. For example HTTP/1.1 requires a host to be specified either in the Host header or as part of the URI on the request line.


Unauthorized. The user requested a document but did not provide a valid user name or password. 


Forbidden. Access to this URL is forbidden. 


Not found. The document requested is not on the server. This code can also be sent if the server is configured to protect the document for unauthorized personnel. 


If the client starts a request but does not complete it within the keep-alive timeout configured in the server, then this response will be sent and the connection closed. The request can be repeated with another open connection. 


The client submitted a POST request with chunked encoding, which is of variable length. However, the resource or application on the server requires a fixed length - a Content-Length header to be present. This code tells the client to resubmit its request with Content-Length.


Some applications, for example, certain NSAPI plug-ins cannot handle very large amounts of data, so returns this error code. 


The URI is longer than the maximum the web server is willing to serve. 


Data was requested outside the range of a file. 


A server-related error occurred. The server administrator must check the error log in the server. 


Sent if the quality of service mechanism was enabled and bandwidth or connection limits were attained. The server then serves requests with that code.