When a browser sends a request to a web server for a file, the response also contains a "status code". Some of these codes carry information about errors, others are informational messages.
Instructions
Step 1
First you need to find out if the code you want to find out is an error code. Codes with numbers from 100 to 399 in server responses do not carry error messages, and the range from 400 to 599 is allocated to inform the browser about problems that have arisen when trying to fulfill its request. If the number you are interested in is greater than 399, then this is indeed an error code. They are divided into two groups, each with 100 numbers.
Step 2
If the required number belongs to the range from 500 to 599, then it indicates one of the following server errors:
500 Internal Server Error - This code means that there was an internal server software failure while processing the request.
501 Not Implemented - the server could not recognize the request method, or the requested function is not supported.
502 Bad Gateway - the failure occurred not at the location where the requested file was stored, but at the routing equipment.
503 Service Unavailable - at the time of the request, one or more server services are unavailable.
504 Gateway Timeout - The server used as a routing gateway has timed out.
505 HTTP Version Not Supported - The HTTP version specified in the request is not supported by this server.
Step 3
Other error codes:
400 Bad Request - an error in the browser request.
401 Unauthorized - the user is not authorized to access the requested file.
402 Payment Required - This error code is currently not used.
403 Forbidden - for some reason the server cannot fulfill the request.
404 Not Found - the requested resource is not available at the specified address.
405 Method Not Allowed - the method specified in the request is not provided for the requested resource.
406 Not Acceptable - there are no objects in the browser request that the server can agree with its response.
407 Proxy Authentication Required - authorization of the user using proxy access to the requested resource is required.
408 Request Timeout - the browser request did not meet the allotted time.
409 Conflict - there is a conflict between the request and the current state of the resource requested by the browser.
410 Gone - the requested resource has been deleted irrevocably.
411 Length Required - the header part of the request does not specify the size of the Content-Length split, and the server requires this with respect to this resource without fail.
412 Precondition Failed - the request specifies the size of the partition, which exceeds the allowable server settings.
413 Request Entity Too Large - the request is too large and therefore is not processed by the server.
414 Request-URI Too Long - the length of the address specified in the request exceeds the maximum allowed.
415 Unsupported Media Type - the format of the object specified in the request is not supported by the server.
416 Requested Range Not Satisfiable - the range specified in the request could not be accepted by the server for execution.
417 Expectation Failed - Timeout expired.
