Hi Erel,
Great to me you. Below is my MessageReceived function. It does display a popup message on my phone with the phone number of the person that sent the text whenever one comes in, but no autoreply is ever sent back to the person. There are no error messages.
Sub SI_MessageReceived (From As String, Body As String) As Boolean
Log("Message From: " & From)
ToastMessageShow(From, True)
Log("Message Was Shown")
Dim smstxt As PhoneSms
smstxt.Send(From,"Test Autoreply")
End Sub