/// <summary>
/// Requeries a previously issued token. Can be used if the client only stores
/// <see cref="TransferToken.TransferId"/> values rather than the tokens and
/// needs to get ahold of them again.
/// </summary>
/// <param name="transferId"></param>
/// <returns></returns>
/// <exception cref="UnknownTransferException">In case the <paramref name="transferId"/>
/// does not refer to an active transfer.</exception>
public DownloadToken ReloadToken(string transferId)
{
return(SecureFunc(FileSystemTask.DownloadTokenRequery,
() => ReaderService.ReloadToken(transferId),
() => String.Format("Could not requery the download token for transfer [{0}].", transferId)));
}