"Value does not fall within the expected range"

Dear All,
We are trying set Expiry Date to file objects and getting the error "Value does not fall within the expected range"

Please check the code below and guide

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using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Office.Core;
using ExcelInterop = Microsoft.Office.Interop.Excel;
using Microsoft.Office.Interop.Word;


class Program
{
private void ImposeExpiryDate()
{

//For Excel
ExcelInterop.ApplicationClass excel = new Microsoft.Office.Interop.Excel.ApplicationClass ();

ExcelInterop.WorkbookClass workBook = (ExcelInterop.WorkbookClass)excel.Workbooks.Open( "c:\\test.xls", 0, true, 5, "" , "", true, ExcelInterop. XlPlatform .xlWindows, "\t", false, false , 0, true, 1, 0);
ExcelInterop.Sheets sheets = workBook.Worksheets;

DateTime dtExpirationDate = DateTime.Today.AddDays(2);
try
{
workBook.Permission.Add(@"[email protected]" ,Microsoft.Office.Core.MsoPermission.msoPermissionFullControl, dtExpirationDate);
}

catch (Exception EX)
{
// "Value does not fall within the expected range" ???
}


//For Word
// Microsoft.Office.Interop.Word.ApplicationClass WordApp =
// new Microsoft.Office.Interop.Word. ApplicationClass ();
// Microsoft.Office.Interop.Word.Document aDoc =
// WordApp.Documents.Open(ref fileName, ref missing,
// ref readOnly, ref missing, ref missing, ref missing,
// ref missing, ref missing, ref missing, ref missing,
// ref missing, ref isVisible);

// aDoc.Permission.Add
// ("[email protected]" ,
// Microsoft.Office.Core.MsoPermission.msoPermissionFullControl,
// dtExpirationDate);
}

}




Regards
Sachin