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Note that to understand if the message has been accepted by the gateway is recommend that you do one document status query. It is recommended that is done not sooner that 1 sec after the send process. If done earlier you may get a -230 error saying the document Id does not exist. If you do get this error you can repeat the request until a non error response is returned. (assuming you are quering the correct documentId under the correct username and pw)
Add new push API for sending delivery status change to the customer:h.3 Coniguring a User for Push Status
1. Push method will be invoked if the check flag in the MCUser record is checked and the address is filled with an http.
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