Hi Yow,
you can't open a wmf file in excel with workbooks.open(). You have to import the image file into a worksheet.
Not tested example: (creates a new workbook and inserts the image)
lole_excel = CREATE OLEObject
lole_excel.ConnectToNewObject( "excel.application" )
lole_excel.visible = true
lole_excel.workbooks.add()
lole_sheet = lole_excel.ActiveSheet
dw_1.SaveAs('C:\.....reports\Graph.wmf',wmf!,TRUE)
lole_sheet.Shapes.addPicture("C:\.....reports\Graph.wmf", 0, -1, left, right, width, height)
see excel vba documentation for more information
