An error occured during importing the selected file

Message:
Seqüência de entrada não estava em um formato incorreto.

StackTrace:
   em System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
   em System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
   em ASToFra.ObjectReader.XReader.ProcessXCommand(XCommand command)
   em ASToFra.ObjectReader.XReader.ProcessXCommand(XCommand command)
   em ASToFra.ObjectReader.XReader.ProcessXCommand(XCommand command)
   em ASToFra.ObjectReader.XReader.ProcessXCommand(XCommand command)
   em ASToFra.ObjectReader.XReader.BuildObjectModel(XCommand xRoot)
   em ASToFra.ObjectReader.XReader.Read(String filename)
   em ASToFra.ObjectReader.AllObjectReader.Read(String fileName)
   em ASToFra.ModelConverterX.MainWindow.bwImporter_DoWork(Object sender, DoWorkEventArgs e)