HTTP status code interpretation

1xx:Message

Messages	Description
100 Continue	The server receives only part of the request, but once the server does not reject the request, the client should continue to send the rest of the request.
101 Switching Protocols	Server conversion protocol: The server will comply with the client's request and convert to another protocol.

2xx: Success

Messages	Description
200 OK	Request successful (followed by response documents to GET and POST requests.)
201 Created	The request is created and new resources are created.
202 Accepted	The request for processing has been accepted, but processing is not completed.
203 Non-authoritative Information	The document has been returned normally, but some response headers may be incorrect because a copy of the document is used.
204 No Content	No new documents. The browser should continue to display the original document. This status code is useful if the user refreshes the page regularly and the servlet can determine that the user's document is current enough.
205 Reset Content	No new documents. But the browser should reset what it displays. Used to force the browser to clear form input content.
206 Partial Content	The client sends a GET request with the Range header and the server completes it.

3xx: redirect

Messages	Description
300 Multiple Choices	Multiple choices. Linked list. Users can select a link to reach their destination. A maximum of five addresses are allowed.
301 Moved Permanently	The requested page has been moved to the new url.
302 Found	The requested page has been temporarily moved to the new url.
303 See Other	The requested page can be found under another URL.
304 Not Modified	Document not modified as expected. The client has a buffered document and makes a conditional request (usually by providing an If-Modified-Since header to indicate that the client only wants documents that are newer than the specified date). The server tells the client that the original buffered document can continue to be used.
305 Use Proxy	Documents requested by the client should be retrieved through the proxy server specified by the Location header.
306 Unused	This code was used in the previous version. It is no longer in use, but the code is still retained.
307 Temporary Redirect	The requested page has been temporarily moved to a new URL.

4xx: Client error

Messages	Description
400 Bad Request	The server failed to understand the request.
401 Unauthorized	The requested page requires a username and password.
401.1	Login failed.
401.2	Server configuration causes login failure.
401.3	Not authorized due to ACL restrictions on resources.
401.4	Filter authorization failed.
401.5	ISAPI/CGI application authorization failed.
401.7	Access is denied by the URL authorization policy on the web server. This error code is specific to IIS 6.0.
402 Payment Required	This code is not available yet.
403 Forbidden	Access to the requested page is prohibited.
403.1	Execution access is prohibited.
403.2	Read access is prohibited.
403.3	Write access is prohibited.
403.4	Requires SSL.
403.5	Requires SSL 128.
403.6	IP address rejected.
403.7	Require client certificate.
403.8	Site access denied.
403.9	Too many users.
403.10	Invalid configuration.
403.11	Password change.
403.12	Access to mapping table is denied.
403.13	Client certificate revoked.
403.14	Reject directory listings.
403.15	Client access permission exceeded.
403.16	Client certificate is not trusted or invalid.
403.17	The client certificate has expired or is not yet valid.
403.18	The requested URL cannot be executed in the current application pool. This error code is specific to IIS 6.0.
403.19	CGI cannot be performed for clients in this application pool. This error code is specific to IIS 6.0.
403.20	Passport login failed. This error code is specific to IIS 6.0.
404 Not Found	The server cannot find the requested page.
404.0	(None) – No file or directory found.
404.1	The website cannot be accessed on the requested port.
404.2	Web service extension locking policy blocks this request.
404.3	MIME mapping policy blocks this request.
405 Method Not Allowed	The method specified in the request is not allowed.
406 Not Acceptable	The server-generated response was not acceptable to the client.
407 Proxy Authentication Required	Users must first authenticate using a proxy server so the request will be processed.
408 Request Timeout	The request exceeded the server's wait time.
409 Conflict	The request could not be completed due to a conflict.
410 Gone	The requested page is unavailable.
411 Length Required	"Content-Length" is not defined. Without this content, the server will not accept the request.
412 Precondition Failed	The precondition in the request was evaluated as failed by the server.
413 Request Entity Too Large	The server will not accept the request because the requested entity is too large.
414 Request-url Too Long	The server will not accept the request because the url is too long. This happens when a POST request is converted into a GET request with very long query information.
415 Unsupported Media Type	The server will not accept the request because the media type is not supported.
416 Requested Range Not Satisfiable	The server cannot satisfy the Range header specified by the client in the request.
417 Expectation Failed	Execution failed.
423	Locked bugs.

5xx: Server error

Messages	Description
500 Internal Server Error	The request is not completed. The server encountered an unpredictable situation.
500.12	The application is busy restarting on the web server.
500.13	The web server is too busy.
500.15	Direct requests to Global.asa are not allowed.
500.16	UNC authorization credentials are incorrect. This error code is specific to IIS 6.0.
500.18	URL authorization storage cannot be opened. This error code is specific to IIS 6.0.
500.100	Internal ASP error.
501 Not Implemented	The request is not completed. The server does not support the requested functionality.
502 Bad Gateway	The request is not completed. The server received an invalid response from the upstream server.
502.1	CGI application timeout. ·
502.2	CGI application error.
503 Service Unavailable	The request is not completed. The server is temporarily overloaded or down.
504 Gateway Timeout	Gateway timeout.
505 HTTP Version Not Supported	The server does not support the HTTP protocol version specified in the request.