123Webmaster.com : Onsite : Reference
Error Code and Status Messages

by William Crooks (appended by Jason M. DesRoches)
The following is a table of error and status messages that you may see when trying to visit a webpage, and the explanations behind theses messages.
200 Ok Your request has succeeded without error.
201 Created The POST request has been done.
202 Accepted The asynchronous request was received but not necessarily acted upon.
204 No Content Request succeeded, but there is nothing to display.
300 Multiple Choices The requested resource is available from multiple places.
301 Moved Permanently Document has been moved permanently. Use new URL.
302 Moved Temporarily Document has been moved temporarily. For the mean time use new URL,
but all references should be to the old URL.
304 Not Modified  Get request worked, but it contains content not modified since the set date.
400 Bad Request Request not understood, modify the syntax of your request and try again.
401 Unauthorized You are not authorized to view the selected document.
402 Payment Required Retry your request after a charge to the header has been made.
403 Forbidden Server refused to grant your request. Your authorization may not have been authenticated. The file does not have "read permissions" set for all users.
404 Not Found The document was not found on the server. (here may be an error in the  URL that you typed, or the document may no longer exist in that location.
405 Method Not Allowed The specified method of request is not allowed for the identified resource.
406 Not Acceptable The requested resource is in an invalid format according to the accept headers.
407 Proxy Authentication Required You are unauthorized to view the requested document, unless you can authenticate yourself with the proxy.
408 Request Timeout The request that you made has taken longer then the server is set to wait. You should make a new request.
409 Conflict A conflict has occurred between your request and a server resource. You should make a new request.
410 Gone The resource is no longer found on the server. All links to this resource should be removed, further access should not be attempted.
411 Length Required You may not access this information without supplying the content length in your request header.
412 Precondition Failed A header precondition has failed to meet the criteria of the client.
412 Request Entity Too Large The server has closed the connection because the requested resource was larger then settings would allow.
414 Request-URI Too Long The requested URI is larger then the server would process.
415 Unsupported Media Type The format of the request was not supported by the requested resource.
500 Internal Server Error An error has occurred with the server. Your request could not be processed.
501 Not Implemented Server does not support your request.
502 Bad Gateway The proxy server received an invalid response from the contacted server.
503 Service Unavailable The server is temporarily unable to handle the request.
504 Gateway Timeout The server did not receive a request from its provider, and has closed the connection.
505 HTTP Version Not Supported The server does not support the HTTP protocol version that was used.

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