Блокировка CD

procedure TMainForm.CD_Lock(Locked: Boolean, DriveLetter: string);
const
  IOCTL_STORAGE_MEDIA_REMOVAL = $002D4804;
var
  hDrive: THandle;
  Returned: DWORD;
  DisableEject: boolean;
begin
  hDrive := CreateFile(PChar('\\.\' + DriveLetter), GENERIC_READ,
    FILE_SHARE_READ, nil, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,
    0);
  if GetLastError <> 0 then
    MessageDlg('Error:' + IntToStr(GetLastError), mtError, [mbOK], 0);
  try
    DisableEject := Locked;
    if not DeviceIoControl(hDrive,
      IOCTL_STORAGE_MEDIA_REMOVAL, // PREVENT_MEDIA_REMOVAL,
      @DisableEject,
      SizeOf(DisableEject),
      nil,
      0,
      Returned,
      nil) then
      MessageDlg('Ошибка:' + IntToStr(GetLastError), mtError, [mbOK], 0)
  finally
    CloseHandle(hDrive)
  end;
end;

procedure TMainForm.LockCDROMs;
var
  w: dword;
  Root: string;
  i: byte;
begin
  w := GetLogicalDrives;
  Root := '#:\';
  for i := 0 to 25 do
  begin
    Root[1] := Char(Ord('A') + i);
    if (W and (1 shl i)) > 0 then
      if GetDriveType(PChar(Root)) = DRIVE_CDROM then
      begin
        DriveLetter := Copy(Root, 1, Length(Root) - 1);
        CD_Lock(True, DriveLetter)
      end
  end;
end;