Hello,
As the official article specifies, the SMS API requisite is Windows 10, thus implying that Windows 11 is not part of the supported scenarios.
Reference: https://learn.microsoft.com/en-us/samples/microsoft/windows-universal-samples/smssendandreceive/
In most case scenarios, this may be a function disabled in later releases due to security or vulnerability potential, or a change in the classes involved in the UWP functions.
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