When you visit a website and get a three-digit number. For many people, those three little numbers mean very little. However, knowing the most common error codes will lead you to greater understanding about when your favorite site might be back up and running again. It is equally important for website owners, marketers, salespeople and IT specialists to know what the error codes mean.
What causes an error message to appear on a website?
Often times when a website gives an error code the reason is quite simple. For example, when we look for a website its URL will be converted into an IP address. If the search engine matches it to one that host more than one site and has room in available server space, it transfers the request to our desired website. When there is a problem, we get one of the following error codes, which indicate the specific issue with the URL or website. There are two types of error messages, the client-side, and the server-side.
In a response from a server, the status code element is a 3 digit integer where the first digit of the status code defines its class. The first digit can be any of the following:
- 1xx Informational Status Codes: The request has been received and is still being processed.
- 2xx Success Status Codes: The action was successfully received, understood, and accepted.
- 3xx Redirection Status Codes: It means further action must be taken in order to complete the request.
- 4xx Client Error Status Codes: The request contains incorrect syntax and cannot be fulfilled.
- 5xx Server Error Status Codes: It means the server failed to process your request.
1xx Information Status Codes:
- 100 Status Code (Continue): The server is not rejecting the request when only a partial message has been received- this means that the client should continue to send messages.
- 101 Status Code (Switching Protocols): The server switches to a new protocol.
2xx Successful Status Codes:
- 200 Status Code (OK): The request is acceptable and OK.
- 201 Status Code (Created Status Code): The request is fulfilled and a new resource is generated.
- 202 Status Code (Accepted Status Code): The request is in the processing phase, but not completed yet.
- 203 Status Code (Non-authoritative Information): The information in the entity header is not from the original server.
- 204 Status Code (No Content): A response to a request with a status code and headers but not entity-body.
- 205 Status Code (Reset Content): The browser should clear the form used for this transaction after it has been parsed.
- 206 Status Code (Partial Content): The server is returning incomplete data. In response to a request specifying the Range header, the server must specify in its Content-Range headers exactly what range of content it will provide in this response.
3xx Redirection Status Codes:
- 300 Status Code (Multiple Choices): A link list with five links, the user selects a link to jump to that location.
- 301 Status Code (Moved Permanently): The page you were looking for has been moved to the following URL
- 302 Status Code (Found): This page has been temporarily re-routed.
- 303 Status Code (See Other): The page you are looking for can be found at another url.
- 304 Status Code (Not Modified): When a page has not been updated since the specified date, this is the response code sent as an HTTP If-Modified-Since or If-None-Match header.
- 305 Status Code (Use Proxy): You must use the proxy specified in the Location header to access this URL.
- 306 Status Code (Unused): The code was previously used in a past version. However, it is no longer in use and the code is reserved.
- 307 Status Code (Temporary Redirect): The requested page is temporarily located at a new url.
4xx Client Error Status Codes:
- 400 Error Code (Bad Request): It appears the server has not understood the request.
- 401 Error Code (Unauthorized): Enter a username and password to access the requested page.
- 402 Error Code (Payment Required): This code is not usable yet.
- 403 Error Code (Forbidden): Access to the requested page is forbidden.
- 404 Error Code (Not Found): The requested page cannot be found.
- 405 Error Code (Method Not Allowed): The desired method specified in the request is not permitted.
- 406 Error Code (Not Acceptable): Unacceptable messages sent from the server to the client.
- 407 Error Code (Proxy Authentication Required): This request cannot be completed without first authenticating with a proxy server.
- 408 Error Code (Request Timeout): The request took too long for the server to wait.
- 409 Error Code (Conflict): The request could not be completed because it conflicted with another request.
- 410 Error Code (Gone): The page you requested is unavailable.
- 411 Error Code (Length Required): The "Content-Length" header must be included with this request.
- 412 Error Code (Precondition Failed): The pre condition in your request evaluated to false.
- 413 Error Code (Request Entity Too Large): The server has refused the request because the entity is too large.
- 414 Error Code (Request-url Too Long): The server is refusing the request because the URL is too long. This error occurs when you convert a "post" request to a "get" request with an excessively long query information.
- 415 Error Code (Unsupported Media Type): The server will not process the request because the media type is unsupported.
- 416 Error Code (Requested Range Not Satisfiable): The requested byte range is not available and is out of bounds.
- 417 Error Code (Expectation Failed): The expectation in an Expect request-header field could not be met by this server.
5xx Server Error Status Codes:
- 500 Error Code (Internal Server Error): This request was not completed. There were issues with the server's connectivity.
- 501 Error Code (Not Implemented): The request was unsuccessful. The server did not provide the requested functionality.
- 502 Error Code (Bad Gateway): The message was not received. The server did not receive a valid response from the upstream server.
- 503 Error Code (Service Unavailable): The request was not completed. The server is currently overloaded or down.
- 504 Error Code (Gateway Timeout): The gateway is not responding.
- 505 Error Code (HTTP Version Not Supported): The server does not support the "HTTP protocol" version.