Excel Instance

New Project, Console Application
References, Add Reference, Assemblies > Extensions
Add "Microsoft.Office.Interop.Excel"
Add the following code:

using Excel = Microsoft.Office.Interop.Excel; 

try 
{ 
   Excel.Application oExcelApplication; 
   Excel.Workbook oWorkbook; 
   Excel.Worksheet oWorksheet; 

   oExcelApplication = new Excel.Application(); 
   oExcelApplication.Visible = true; 
   oWorkbook = oExcelApplication.Workbooks.Add(); 
   oWorksheet = oWorkbook.Sheets[1]; 
   oWorksheet.Name = "New Worksheet"; 

   for (long lRowNo = 1; lRowNo < 6; lRowNo++) 
   { 
      oWorksheet.get_Range("A" + lRowNo).Value = lRowNo * 10; 
   } 
   oWorksheet.get_Range("A" + 6).Formula = "=SUM(A1:A5)"; 
   oWorkbook.SaveAs(@"C:\temp\MyFile.xlsx"); 

   oExcelApplication.Quit(); 
} 
catch(System.Runtime.InteropServices.COMException ex) 
{ 
   System.Console.WriteLine(ex.ErrorCode.ToString() + " - " + ex.Message); 
} 

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