When you download the source code from [caption id=“attachment_10266” align=“alignnone” width=“610” caption=“Export GridView Data to Excel using OpenXml”][/caption] http://www.codeproject.com/Tips/366446/Export-GridView-Data-to-Excel-using-OpenXml and try to transfer it to Excel from a single cell to another Excel file,  it is not easy. I have broken a big chunk into a smaller unit to just output one value to an Excel workbook using OpenXML SDK. Below is the part of code segments that doing this. //Simple private void CreateExcelParts(SpreadsheetDocument spreadsheetDoc, string str) { //Create a Workbook WorkbookPart workbookPart = spreadsheetDoc.AddWorkbookPart(); CreateWorkbookPart(workbookPart); //Create a worksheet Worksheet worksheet = new Worksheet() { MCAttributes = new MarkupCompatibilityAttributes() { Ignorable = “x14ac” } }; worksheet.AddNamespaceDeclaration(“r”, “http://schemas.openxmlformats.org/officeDocument/2006/relationships"); worksheet.AddNamespaceDeclaration(“mc”, “http://schemas.openxmlformats.org/markup-compatibility/2006"); worksheet.AddNamespaceDeclaration(“x14ac”, “http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac");   //Create sheetviews SheetViews sheetViews = new SheetViews(); SheetView sheetView = new SheetView() { WorkbookViewId = (UInt32Value)0U }; //Create a cell or range Selection selection = new Selection() { ActiveCell = “A1” }; //Append range to sheetview sheetView.Append(selection); //Append sheetview to sheetviews sheetViews.Append(sheetView);   int columnIndex = 0;   SheetData sheetData = new SheetData();   UInt32Value rowIndex = 1U; //Create a row Row row1 = new Row() { RowIndex = rowIndex++, Spans = new ListValue() { InnerText = “1:3” }, DyDescent = 0.25D }; //Create a cell and put the value in it Cell cell = new Cell() { CellReference = ExcelHelper.ColumnCaption.Instance.Get((Convert.ToInt32((UInt32)rowIndex) - 2), columnIndex), DataType = CellValues.String }; CellValue cellValue = new CellValue(); //Create a CellValue to store the value //Assign the value to new cell cellValue.Text = str; //Append the cellValue into cell cell.Append(cellValue); //Append the cell to row row1.Append(cell); //Append the row to sheetdata sheetData.Append(row1); //Append the sheetData to worksheet worksheet.Append(sheetData); WorksheetPart worksheetPart = workbookPart.AddNewPart(“rId” + (101).ToString()); //Append the worksheet into workbook workbookPart.WorksheetParts.ElementAt(0).Worksheet = worksheet; //Save the workbook workbookPart.Workbook.Save(); }   ///

/// Creates the workbook part. ////// The workbook part. private void CreateWorkbookPart(WorkbookPart workbookPart) { Workbook workbook = new Workbook(); Sheets sheets = new Sheets();   Sheet sheet = new Sheet() { Name = “Book” + 1, SheetId = Convert.ToUInt32(101), Id = “rId” + (101).ToString() }; sheets.Append(sheet);   CalculationProperties calculationProperties = new CalculationProperties() { CalculationId = (UInt32Value)123456U  // some default Int32Value }; workbook.Append(sheets); workbook.Append(calculationProperties); workbookPart.Workbook = workbook; }   The code segment is pretty much self-explanatory. You can also download a single solution from http://skydrive.live.com. The sample file name is GridToExcelNew.rar If you have any questions, feel free to ping me. My  MSN ID is chanmmn@hotmail.com.