A>The problem occurs because ATL's implementation of IPersistStreamInit::Save and IPersistStreamInit::Load performs a QueryInterface call to get the IDispatch of the root control from which it will persist stock properties. Because Word wraps all embedded controls in an aggregated extender object, the QueryInterface call is returning the IDispatch of the Word extender and not the internal control. This causes the persist methods to fail when saving and loading the control in certain circumstances.