Com Object That Has Been Separated From Its Underlying Rcw Cannot Be Used

using System;
using System.Collections.Generic;
using Microsoft.Office.Tools.Excel;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Data.Odbc;
using System.Data;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using Excel = Microsoft.Office.Interop.Excel;
using Range = Microsoft.Office.Interop.Excel.Range;
using Worksheet = Microsoft.Office.Interop.Excel.Worksheet;
// Fred Liu. Wednesday June 11, 2012-

// Need to do custom swaps

namespace Fills2010
{
    public class IRSwaps
    {
        public IRSwaps(BookRangeSettings sett, SqlDataTools sqltools)
        {
            try
            {                
                m_xl = sett;
                m_dataTools = sqltools;
                ((Excel.Worksheet)Globals.ThisAddIn.Application.ActiveWorkbook.Sheets["CAD_IR_Swaps"]).Select(Type.Missing);
                general("Standard", "virs", false, "B1", "K115");
                general("Overnight", "OIS", false, "E1", "K17");
                general("Monthly", "irs_31", false, "B1", "C13");
                zeros(false, "E1", "J249");
                FRAs();
                custom();
                ((Excel.Worksheet)Globals.ThisAddIn.Application.ActiveWorkbook.Sheets["CAD_IR_Swaps"]).Calculate();

                // USD IRS
                ((Excel.Worksheet)Globals.ThisAddIn.Application.ActiveWorkbook.Sheets["US_IR_Swaps"]).Select(Type.Missing);
                general("Standard", "VIRS_US", true, "B1", "K229");
                zeros(true, "E1", "J5");
                ((Excel.Worksheet)Globals.ThisAddIn.Application.ActiveWorkbook.Sheets["US_IR_Swaps"]).Calculate();
            }
            catch (Exception exp)
            {
                MessageBox.Show("Fills 2010: Error getting index options " + exp.Message + "\n Stack: " + exp.StackTrace);
            }
        }

        private void general(string type, string namedRange, bool isUSD, string startRangeFormat, string endRangeFormat)
        {

        }

        private void format(string startRange, string endRange, Range output)
        {
            // 2 letters ahead since columns A and B are empty
            Range format = (Range)(output.get_Range(startRange, endRange));
            format.NumberFormat = "_(* #,##0.00_);_(* (#,##0.00);_(* \" - \"??_);_(@_)";
        }

        private void zeros(bool isUSD, string startRangeFormat, string endRangeFormat)
        {

        }

        private void FRAs()
        {

        }

        private void custom()
        {
            DateTime rangeReportDate = DateTime.Parse(m_xl.NamedRange("sdate").Text.ToString());
            Range output = m_xl.NamedRange("CIRS");
            string sql = "SQL here";
            ADODB.Recordset rds = m_dataTools.Query_SF(sql);
            output.ClearContents();
            output.CopyFromRecordset(rds, Type.Missing, Type.Missing);
            format("C1", "K5000", output); // Formats the cells as currency
            format("N1", "O5000", output);
            format("Q1", "R5000", output);
            format("U1", "V5000", output);

            string date = m_xl.Range("CAD_IR_Swaps", "E1581").Value2.ToString();
            bool ignore = false;
            int legs = 1;
            for (int i = 1581; i < rds.RecordCount + 1580; i++) // Starting row
            {
                /* ERROR POSSIBLE */ string currentDate = m_xl.Range("CAD_IR_Swaps", "E" + i.ToString()).Value2.ToString();
                string nextDate = currentDate;
                if (m_xl.Range("CAD_IR_Swaps", "E" + (i + 1).ToString()).Value2 != null)
                /* ERROR POSSIBLE */     nextDate = m_xl.Range("CAD_IR_Swaps", "E" + (i + 1).ToString()).Value2.ToString();

                // If not 1st row and the current row's trade date is the same as the last row (i.e. same swap)
                if (i > 1581 && currentDate == date)
                {
                    if (ignore == false)
                    {
                        /* ERROR POSSIBLE */ m_xl.Range("CAD_IR_Swaps", "C" + i.ToString() + ":M" + i.ToString()).ClearContents();
                        legs++;
                    }
                    else
                        ignore = false;
                }
                if (nextDate != date || i >= rds.RecordCount + 1580)
                {
                    if (nextDate != null)
                    {
                        ignore = true;
                        date = nextDate;
                    }
                    m_xl.Range("CAD_IR_Swaps", "M" + (i - legs + 1).ToString()).Value2 = legs;
                    m_xl.Range("CAD_IR_Swaps", "T" + (i - legs + 1).ToString()).Value2 = legs;
                    legs = 1;
                }
            }
            // Get rid of the last row
            m_xl.Range("CAD_IR_Swaps", "C" + (rds.RecordCount + 1580).ToString() + ":M" + (rds.RecordCount + 1580).ToString()).ClearContents();

            // Count the last swap
            legs = 1;
            int k = 1580 + rds.RecordCount;
            while (m_xl.Range("CAD_IR_Swaps", "E" + k.ToString()).Value2 == null)
            {
                k--;
                legs++;
            }
            m_xl.Range("CAD_IR_Swaps", "M" + (1580 + rds.RecordCount - legs + 1).ToString()).Value2 = legs;
            m_xl.Range("CAD_IR_Swaps", "T" + (1580 + rds.RecordCount - legs + 1).ToString()).Value2 = legs;
        }

        private BookRangeSettings m_xl;

        private SqlDataTools m_dataTools;
    }
}