不用api的,改注册表。
{  功能描述:WINDOWS启动时程序自动运行  }
procedure TMainForm.AddToRun;
var
  reg:TRegistry;
begin
  reg:=TRegistry.Create;
  try
    reg.RootKey:=HKEY_LOCAL_MACHINE;
    reg.OpenKey('Software\Microsoft\Windows\CurrentVersion\Run',false);
    reg.WriteString('backup',Application.ExeName+' m');
    reg.CloseKey;
  finally
    reg.Free;
  end;    
end;