I’ll provide a brief overview of server error codes in this article. Plus, I’ll provide you with a list of server error codes and their meanings. This information may be helpful for investigators who are looking into cyber crime, online fraud, and corporate espionage.
What is a Server Error Code?
When a web browser requests a service from a web server, there is always a possibility that an error might occur. When an error does occur, the webserver returns a response in the form of a Hypertext Transfer Protocol (HTTP) Status Code to the user. These status codes are commonly known as server error codes. Server error codes are standard and will appear regardless of the web browser being used (i.e. Google Chrome, Internet Explorer, Safari, etc.).
Private investigators who conduct computer forensic investigations should be able to understand and interpret these types of codes during the course of an investigation case. The following information will help serve as a reference for decoding the information.
What are the Codes used for?
The purpose of the codes is to help identify the problem when a web page or web page element does not load properly. The problem could originate on the server itself, or have something to do with the HTML, Javascript, CSS, PHP, or other types of code on the page the user is trying to view.
The information provided can be helpful to the user, but it is especially helpful to the site’s webmaster or owner. The site’s webmaster can use the error code to troubleshoot and hopefully fix the problem so it doesn’t happen again. A website that is free of error codes offers a better experience for the end user.
Code Categories
Hypertext Transfer Status Codes are three-digit codes that fall into five major categories (see the list of server error codes below for examples of each type):
- 1xx: Informational – Codes in this category indicate the request was received, continuing the process
- 2xx: Success – The action was successfully received, understood, and accepted
- 3xx: Redirection – Further action must be taken in order to complete the request
- 4xx: Client Error – The request contains bad syntax or cannot be fulfilled
- 5xx: Server Error – The server failed to fulfill an apparently valid request
Typically, users and web browsers do not see status codes that begin with 1, 2, or 3. Typically, users only see HTTP error codes beginning with 4 or 5.
List of Error Code Messages
- 100 = Continue
- 101 = Switching Protocols
- 102 = Processing
- 200 = OK
- 201 = Created
- 202 = Accepted
- 203 = Non-authoritative Information
- 204 = No Content
- 205 = Reset Content
- 206 = Partial Content
- 207 = Multi-Status
- 208 = Already Reported
- 226 = IM Used
- 300 = Multiple Choices
- 301 = Moved Permanently (used with redirects)
- 302 = Found
- 303 = See Other
- 304 = Not Modified
- 305 = Use Proxy
- 307 = Temporary Redirect
- 308 = Permanent Redirect
- 400 = Bad Request
- 401 = Unauthorized
- 402 = Payment Required
- 403 = Forbidden
- 404 = Not Found
- 405 =Method Not Allowed
- 406 = Not Acceptable
- 407 = Proxy Authentication Required
- 408 = Request Timeout
- 409 = Conflict
- 410 = Gone
- 411 = Length Required
- 412 = Precondition Failed
- 413 = Payload Too Large
- 414 = Request-URI Too Long
- 415 = Unsupported Media Type
- 416 = Requested Range Not Satisfiable
- 417 = Expectation Failed
- 418 = I’m a teapot
- 421 = Misdirected Request
- 422 = Unprocessable Entity
- 423 = Locked
- 424 = Failed Dependency
- 426 = Upgrade Required
- 428 = Precondition Required
- 429 = Too Many Requests
- 431 = Request header fields are too large
- 444 = Connection Closed Without Response
- 451 = Unavailable For Legal Reasons
- 499 = Client Closed Request
- 500 = Internal Server Error
- 501 = Not Implemented
- 502 = Bad Gateway
- 503 = Service Unavailable
- 504 = Gateway Timeout
- 505 = HTTP Version Not Supported
- 506 = Variant Also Negotiates
- 507 = Insufficient Storage
- 508 = Loop Detected
- 510 = Not Extended
- 511 = Network Authentication Required
- 599 = Network Connect Timeout Error
Additional Information
HTTP status codes are also browser error codes and internet error messages.
Questions and Comments
If you have any questions about this list of server error codes, please post a comment below. Also, view more Lists of Lists.