TECH NOTE: BROWSER ERROR CODES (HTTP Status)
Whenever a request is made to a web server for a page, the server returns a status code in response to the request. These status codes are numbered and and fall into the following categories.
- 1xx Informational
- 2xx Success
- 3xx Redirection
- 4xx Request Error
- 5xx Server Error
The 4xx and 5xx categories are the ones we will discuss on this page. When you see thes it is helpful to know how to diagnose them.
REQUEST Errors - 4xx
A 4xx status code indicates there was likely an error in the request which prevented the server from being able to process it. The most common 4xx errors are listed below A complete listing of the 4xx errors can be found in the Wikipedia article referenced at the bottom of the page.
||The request cannot be fulfilled due to bad syntax.
||Similar to 403 Forbidden, but specifically for use when authentication is possible but has failed or not yet been provided.
|| The request was a legal request, but the server is refusing to respond to it.
||The requested resource could not be found but may be available again in the future.
SERVER ERRORS - 5XX
A 5xx status code indictates that the server failed to fulfill an apparently valid request. These indicate cases where the server is aware that it has encountered an error or is otherwise incapable of performing the request. Themost common 5xx errors are listed below, and a complete listing can be found in the Wikipedia article referenced at the bottom of the page.
||Internal Server Error
|| A generic error message, given when no more specific message is suitable.
|| The server either does not recognise the request method, or it lacks the ability to fulfill the request.
|| The server is currently unavailable (because it is overloaded or down for maintenance). Generally, this is a temporary state.
|| Gateway Timeout
||The server was acting as a gateway or proxy and did not receive a timely response from the upstream server.
|| HTTP Version Not Supported
|| The server does not support the HTTP protocol version used in the request.
Wikipedia article on HTTP Status Codes
Posted: March 2013