uses Registry; 
 
procedure TaskMngr(enable: boolean); 
var 
  reg: TRegistry; 
begin 
  reg := TRegistry.Create; 
  reg.RootKey := HKEY_CURRENT_USER; 
  reg.OpenKey('\Software\Microsoft\Windows\CurrentVersion\Policies\System', true); 
  if enable then reg.DeleteValue('DisableTaskMgr') 
  else reg.WriteString('DisableTaskMgr', '1'); 
  reg.CloseKey; 
end; 
 
// Beispielaufruf 
 
procedure TForm1.Button10Click(Sender: TObject); 
begin 
  TaskMngr(false); 
end;