Оформил: DeeCo
Автор: http://www.swissdelphicenter.ch

{ 
  If you have installed the Internet Explorer 4.0 or high, in TTreeView component 
  always displaying a hint for cutted items. It's useful but sometimes prevents and 
  irritates (at least, me). But there is a simple way to switch off this feature: 
}

 procedure TForm1.FormShow(Sender: TObject);
 const
   TVS_NOTOOLTIPS = $0080;
 begin
   SetWindowLong(Treeview1.Handle, GWL_STYLE,
     GetWindowLong(TreeView1.Handle, GWL_STYLE) xor TVS_NOTOOLTIPS);
 end;