It apparently breaks down like this. Different controls will actually scroll for you in response to different commands sent via SendMessage().

  • Textbox - SendMessage EM_LINESCROLL; wParam = 0 and lParam = number of lines to scroll
  • Listbox, FileListbox, Treeview, Listview - SendMessage WM_VSCROLL; wParam = SB_BOTTOM (7), SB_LINEDOWN (1), SB_LINEUP (0) and lParam = 0