To better understand what could cause a failure, it is necessary to distinguish between errors reported at HTTP protocol level via HTTP status codes and the ones reported at application level (HUB2 API).

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HTTP error status codes

A HTTP status code in “error” (HTTP 4XX or HTTP 5XX) indicates a communication or request processing problem between an HTTP client and an HTTP server. These codes, included in the server response, indicate the status of the HTTP request. These codes are standardised and must be followed by the server-side application in order to be correctly interpreted by the HTTP client.

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Application errors

On the other hand, there are “application errors” which occur once the HTTP request has been accepted for asynchronous processing (after it has returned an HTTP 2XX status code). These errors are specific to the logic of the HUB2 platform and are communicated via specific error codes defined within the HUB2 application. See also :

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Fix an error

It is important to distinguish between the two types of errors. Understand that HTTP status codes in error indicate a problem during communication (or with the request) between the client and the server, whereas application errors reflect problems encountered during the asynchronous processing of a transaction, outside the context of an HTTP request, only at Hub2 level. The reasons for failure listed on the Application errors pages are only for errors encountered during asynchronous processing of any HTTP request. For more details about which HTTP status code can be returned by the HUB2 API for each endpoint, please refer to the HUB2 API Reference Documentation.