To reproduce: public Form1() { InitializeComponent(); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text1")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text2")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text3")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text4")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text5")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text6")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text7")); radGridView1.Columns.Add(new GridViewTextBoxColumn("Text8")); radGridView1.Columns.Add(new GridViewDateTimeColumn("Date1")); radGridView1.Columns.Add(new GridViewDecimalColumn("Amount1")); radGridView1.Columns.Add(new GridViewDecimalColumn("Amount2")); radGridView1.Columns.Add(new GridViewDecimalColumn("Amount3")); radGridView1.Columns.Add(new GridViewDecimalColumn("Amount4")); radGridView1.Columns.Add(new GridViewDecimalColumn("Amount5")); radGridView1.Columns.Add(new GridViewDecimalColumn("Amount6")); radGridView1.DataSource = GetDataSet(); } private DataTable GetDataSet() { DataTable dt = new DataTable(); dt.Columns.Add(new DataColumn("Text1", typeof(string))); dt.Columns.Add(new DataColumn("Text2", typeof(string))); dt.Columns.Add(new DataColumn("Text3", typeof(string))); dt.Columns.Add(new DataColumn("Text4", typeof(string))); dt.Columns.Add(new DataColumn("Text5", typeof(string))); dt.Columns.Add(new DataColumn("Text6", typeof(string))); dt.Columns.Add(new DataColumn("Text7", typeof(string))); dt.Columns.Add(new DataColumn("Text8", typeof(string))); dt.Columns.Add(new DataColumn("Date1", typeof(DateTime))); dt.Columns.Add(new DataColumn("Amount1", typeof(decimal))); dt.Columns.Add(new DataColumn("Amount2", typeof(decimal))); dt.Columns.Add(new DataColumn("Amount3", typeof(decimal))); dt.Columns.Add(new DataColumn("Amount4", typeof(decimal))); dt.Columns.Add(new DataColumn("Amount5", typeof(decimal))); dt.Columns.Add(new DataColumn("Amount6", typeof(decimal))); for (int i = 1; i <= 150000; i++) { dt.Rows.Add(new object[] { "Example Text For Row " + i.ToString(), "Example Text For Row " + i.ToString(), "More Example Text For Row " + i.ToString(), "Even More Example Text For Row " + i.ToString(), "Lots More Example Text For Row " + i.ToString(), "Excessive Example Text For Row " + i.ToString(), "Extra Example Text For Row " + i.ToString(), "Random Example Text For Row " + i.ToString(), new DateTime(2015, i % 12 + 1, i % 28 + 1), i % 2 * 10000, i % 3 * 10000, i % 5 * 10000, i % 7 * 10000, i % 11 * 10000, i % 13 * 10000 }); } return dt; } string fileName = @"..\..\" + DateTime.Now.ToLongTimeString().Replace(":", "_"); private void button1_Click(object sender, EventArgs e) { SaveFileDialog sfdExportToExcel = new SaveFileDialog(); DialogResult exportBrowse = sfdExportToExcel.ShowDialog(); if (exportBrowse == DialogResult.OK) { GridViewSpreadExport exporter = new GridViewSpreadExport(this.radGridView1); exporter.SheetMaxRows = Telerik.WinControls.UI.Export.ExcelMaxRows._1048576; exporter.FileExportMode = FileExportMode.CreateOrOverrideFile; exporter.ExportVisualSettings = false; exporter.AsyncExportCompleted += exporter_AsyncExportCompleted; SpreadExportRenderer renderer = new SpreadExportRenderer(); exporter.RunExportAsync(fileName, renderer); } }