Ok, I'm getting nowhere fast with this. Using this context but it seems the lookup is not working. If I omit the KeyExist the messge gets submitted locally.

IF KeyExist ("HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles\Outlook”)
$RC = SendMessage("ELWY", "Test")
ELSE
?"do nothing"
ENDIF