function ShutdownSystem(bForce: Boolean): Boolean;
var
  Handle: THandle;
  Priveleges: TOKEN_PRIVILEGES;
  Size: Longword;
  luid: int64;
begin
  result := false;

  if not OpenThreadToken(OpenThread(PROCESS_ALL_ACCESS, FALSE, GetCurrentThreadId()), TOKEN_ALL_ACCESS, TRUE, Handle)
  and not OpenProcessToken(GetCurrentProcess(), TOKEN_ALL_ACCESS, Handle) then
    Exit;

  if not LookupPrivilegeValue(nil, 'SeShutdownPrivilege', luid) then
    Exit;

  Priveleges.PrivilegeCount := 1;
  Priveleges.Privileges[0].Luid := luid;
  Priveleges.Privileges[0].Attributes := SE_PRIVILEGE_ENABLED;

  if not AdjustTokenPrivileges(Handle, false, Priveleges, SizeOf(Priveleges), Priveleges, Size) then
    Exit;

  if bForce then
    result := ExitWindowsEx(EWX_FORCE or EWX_POWEROFF, 0) or ExitWindowsEx(EWX_FORCE or EWX_SHUTDOWN, 0)
  else
    result := ExitWindowsEx(EWX_POWEROFF, 0) or ExitWindowsEx(EWX_SHUTDOWN, 0)
end;