The type initializer for 'ClosedXML.Excel.XLWorkbook' threw an exception
<p>`using ClosedXML.Excel;</p>

<p>class XLSXWriter : BExporter
    {
        private readonly string _fName;</p>

<pre><code>    public XLSXWriter(string fileName)
    {
        _fName = fileName;
    }

    public override void Export(IEnumerable&lt;AnimalData&gt; animals)
    {
        var workBook = new XLWorkbook(); &lt;---Throws an exception

        var workSheet = workBook.Worksheets.Add("MySheet");

        workSheet.Cell("A1").Value = "Hello World";            

        FileStream fs = new FileStream(_fName, FileMode.Create);
        workBook.SaveAs(fs);
        fs.Close();          
    }
}`
</code></pre>

<p>Just trying this library ClosedXML.dll, and it throws an exception can't figure out what could be the problem.
I get the _fName from the savefiledialog.
Ideas anybody?</p>
