Why does mapi not apply to M8?

Because "when talking about text message operations on Windows Mobile clients, almost everyone will think of the cemapi interface as soon as possible. It is true that the cemapi interface is currently the most used and the most mature technology, the cemapi interface can be used to conveniently send, receive, and delete text messages, without the need to focus on tedious coding and decoding issues. However, cemapi has its own shortcomings, for example, the cemapi interface is fully implemented based on tmail, And the SMS interception, sending, and Arrival notification operations are ultimately implemented by tmail, which means that, the text message operation module in the program must be completely dependent on the execution status of tmail. For example, if the tmail program is not started, the text message will not be sent immediately after the client executes the submitmessage operation, the text message is sent only after tmail is started. Because the return value of this interface only specifies whether the operation is successful with the text message database, you cannot know whether the text message has been successfully sent in the program." [Note]

Tmail only exists on Windows Mobile systems, rather than Windows CE.

The M8 Short Message program is developed or OEM by itself.

Therefore, mapi does not work on M8.