API Responses


Sidemail uses conventional HTTP response codes to indicate the success or failure of an API request. In general: Codes in the 2xx range indicate success. Codes in the 4xx range indicate that there was an issue with the request that was sent. Among other things, this could mean that you did not authenticate correctly, that you are requesting an action that you do not have authorization for, or that your request is malformed. Codes in the 5xx range indicate a server error on the Sidemail's side.

Response structure




A brief description of the error. Usually contains instruction on how to resolve the issue.


An error code. Search the appropriate section in this API documentation to find out more about the error.


A link to the appropriate documentation.