Error

Error

	Extension '' is not supported. Supported extensions are '.xlsx' and '.xslm'.

Stack Trace	at ClosedXML.Excel.XLWorkbook.GetSpreadsheetDocumentType(String filePath) at Alert.Net.DownloadDocument.Render(HtmlTextWriter writer) at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) at System.Web.UI.Control.RenderControl(HtmlTextWriter writer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
Source	ClosedXML