Launching a New Compose Form
Form server implementers should expect the following sequence of method calls to their form server and form objects when a client application opens a new message for composing:
The client application calls IMAPIFormMgr::ResolveMessageClass to get class information about the form server's message class.
The client application calls IMAPIFormMgr::CreateForm to get a new form object.
The MAPI form manager loads the form server, if it is not already in memory and gets an IMAPIForm object from the form server.
The client application takes the resulting IMAPIForm object and calls the QueryInterface method to get the object's IPersistMessage interface.
The client application calls IPersistMessage::InitNew to associate the form object with IMessage , view context, and advise sink objects.
The client application calls IMAPIForm::DoVerb to invoke the "open" verb.