Function ChangeLogoPicture(ByRef oDoc As Word.Document) As Boolean
Dim oHeader As HeaderFooter
Dim oRng As Range, oRngTarget As Range
Dim oILS As InlineShape
   On Error GoTo Err_Handler
  'Assumes logo is in First Page Header (modify if required)
  Set oHeader = oDoc.Sections(1).Headers(wdHeaderFooterFirstPage)
  Set oRng = oHeader.Range
  If oRng.InlineShapes.Count > 0 Then
      Set oILS = oRng.InlineShapes(1)
      Set oRngTarget = oILS.Range
      oILS.Delete
      Set oILS = ActiveDocument.InlineShapes.AddPicture(FileName:="C:\New Pic.png", linktofile:=False, Range:=oRngTarget)
      With oILS
        'Do whatever you might need to do.
      End With
    End If
  ChangeLogoPicture = True
lbl_Exit:
  Exit Function
Err_Handler:
  ChangeLogoPicture = False
  Resume lbl_Exit
End Function