List of Most 4xx Client Errors and Possible Fixes

This class of status code is intended for situations in which the error seems to have been caused by the client. Except when responding to a HEAD request, the server should include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. These status codes are applicable to any request method. User agents should display any included entity to the user.

400 Bad Request

The server cannot or will not process the request due to an apparent client error (e.g., malformed request syntax, a size too large, invalid request message framing, or deceptive request routing).

401 Unauthorized 

Similar to 403 Forbidden, but specifically for use when authentication is required and has failed or has not yet been provided. The response must include a WWW-Authenticate header field containing a challenge applicable to the requested resource. 401 semantically means “unauthorized”, the user does not have valid authentication credentials for the target resource.

Note: Some sites incorrectly issue HTTP 401 when an IP address is banned from the website (usually the website domain) and that specific address is refused permission to access a website.

402 Payment Required

Reserved for future use. The original intention was that this code might be used as part of some form of digital cash or micropayment scheme, as proposed, for example, by GNU Taler, but that has not yet happened, and this code is not usually used. Google Developers API uses this status if a particular developer has exceeded the daily limit on requests Sipgate uses this code if an account does not have sufficient funds to start a call. Shopify uses this code when the store has not paid their fees and is temporarily disabled. Stripe uses this code for failed payments where parameters were correct, for example, blocked fraudulent payments.

403 Forbidden

The request contained valid data and was understood by the server, but the server is refusing action. This may be due to the user not having the necessary permissions for a resource or needing an account of some sort, or attempting a prohibited action (e.g. creating a duplicate record where only one is allowed). This code is also typically used if the request provided authentication via the WWW-Authenticate header field, but the server did not accept that authentication. The request should not be repeated.

404 Not Found

The requested resource could not be found but may be available in the future. Subsequent requests by the client are permissible.

405 Method Not Allowed

A request method is not supported for the requested resource; for example, a GET request on a form that requires data to be presented via POST, or a PUT request on a read-only resource.

406 Not Acceptable

The requested resource is capable of generating only content not acceptable according to the Accept headers sent in the request. See Content negotiation.

407 Proxy Authentication Required 

The client must first authenticate itself with the proxy.

408 Request Timeout

The server timed out waiting for the request. According to HTTP specifications: “The client did not produce a request within the time that the server was prepared to wait. The client MAY repeat the request without modifications at any later time.

409 Conflict

Indicates that the request could not be processed because of conflict in the current state of the resource, such as an edit conflict between multiple simultaneous updates.

410 Gone

It indicates that the resource requested is no longer available and will not be available again. This should be used when a resource has been intentionally removed and the resource should be purged. Upon receiving a 410 status code, the client should not request the resource in the future. Clients such as search engines should remove the resource from their indices. Most use cases do not require clients and search engines to purge the resource, and a “404 Not Found” may be used instead.

411 Length Required

The request did not specify the length of its content, which is required by the requested resource.

412 Precondition Failed 

The server does not meet one of the preconditions that the requester put on the request header fields.

413 Payload Too LargeThe request is larger than the server is willing or able to process. Previously called “Request Entity Too Large

414 URI Too Long 

The URI provided was too long for the server to process. Often the result of too much data being encoded as a query-string of a GET request, in which case it should be converted to a POST request. Called “Request-URI Too Long” previously.

415 Unsupported Media Type

The request entity has a media type which the server or resource does not support. For example, the client uploads an image as image/svg+xml, but the server requires that images use a different format.

416 Range Not Satisfiable 

The client has asked for a portion of the file (byte serving), but the server cannot supply that portion. For example, if the client asked for a part of the file that lies beyond the end of the file. Called “Requested Range Not Satisfiable” previously.

417 Expectation Failed

The server cannot meet the requirements of the Expect request-header field.

421 Misdirected Request 

The request was directed at a server that is not able to produce a response (for example because of connection reuse).

422 Unprocessable Entity

The request was well-formed but was unable to be followed due to semantic errors.

423 Locked 

The resource that is being accessed is locked.

424 Failed Dependency

The request failed because it depended on another request and that request failed (e.g., a PROPPATCH).