OLE Link to Word 97-2003 File May Fail with OLE_E_CLASSDIFF Error on Open
You may encounter an OLE_E_CLASSDIFF (0x80040008) error on calls to OleRun or IOleObject::DoVerb when attempting to bind to a Word document saved as an OLE link by Word 2007. See the following post for details:
OLE Link to Word 97-2003 File May Fail with OLE_E_CLASSDIFF Error on Open
