# Error handling :white\_check\_mark:Professional :white\_check\_mark:Premium :white\_check\_mark:Enterprise Sending a request to Ultimo Business Integration will return an HTTP response status code. A list of all status codes can be found [here](https://en.wikipedia.org/wiki/List_of_HTTP_status_codes). One important thing to remember: a 200 OK response does not mean that the request was successfully handled by Ultimo. It only means that the request was received successfully by the API. Whenever a request is successfully received, it will be processed separately afterwards. Details of possible errors will be returned in the response body. ## Common HTTP response status codes * `200 OK`, Ultimo has received the web request successfully and tried to process it. Details of the processing results are returned in the response body. * `400 Bad Request`, Ultimo is not able to process the request due to an apparent client error. This usually means there is a malformed request syntax. * `401 Unauthorized`, Ultimo is not able to match the specified authentication parameters * `404 Not found`, the used endpoint is probably incorrect * `500 Internal Server Error`, a generic error that can be caused by many different problems. Depending on the failure, the response body might contain detailed information. ## Error message example When processing of a request fails, the response body will contain detailed information on what went wrong. These error messages are returned in a fixed format and cannot be customised. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://developer.ultimo.net/api-guide/error-handling.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.