Try this:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/odc_vsto2003_ta
/html/odc_VSTMultCR.asp

I have a similar problem

Dear all
I build a new application using c#.net2005 to read excel file I write the following code but it gives me a run time error
((Old format or invalid type library. (Exception from HRESULT: 0x80028018 (TYPE_E_INVDATAREAD))

can any one help me

using System;
using System.Reflection; // For Missing.Value and BindingFlags
using System.Runtime.InteropServices;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Resources;
using Microsoft.Office.Core;
using System.IO;
using System.Configuration;
using System.Data.SqlClient;
using Excel;

namespace ReadExcelFiletest
{
   public partial class Form1 : Form
   {
       private Excel.Application ExcelObj = null;
       private string strConn = "";
       private string[,] myArray = new string[5000, 2];
       private int myarrayindex;
       public Form1()
       {
           InitializeComponent();
       }

       private void btnBrowse_Click(object sender, EventArgs e)
       {
           openFileDialog1.ShowDialog();
           this.txtLocation.Text = openFileDialog1.FileName;
       }

       private void btnUpdate_Click(object sender, EventArgs e)
       {
           // string Path = @"c:\test.xls";
           string MyPath = this.txtLocation.Text.Trim().ToString();

           // initialize the Excel Application class
           Excel.ApplicationClass app = new ApplicationClass();
           // create the workbook object by opening the excel file.
           Excel.Workbook workBook = app.Workbooks.OpenMyPath , 0, true, 5, "", "", true, Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
           // get the active worksheet using sheet name or active sheet
           Excel.Worksheet workSheet = (Excel.Worksheet)workBook.ActiveSheet;
           int index = 0;
           // This row,column index should be changed as per your need.
           // i.e. which cell in the excel you are interesting to read.
           object rowIndex = 1;
           object colIndex1 = 1;
           object colIndex2 = 2;
           object colIndex3 = 3;
           myarrayindex = 0;

           try
           {
               while (((Excel.Range)workSheet.Cells[rowIndex, colIndex1]).Value2 != null)
               {

                   rowIndex = index + 1;
                   string PartNO = ((Excel.Range)workSheet.Cells[rowIndex, colIndex1]).Value2.ToString();
                   string Price = ((Excel.Range)workSheet.Cells[rowIndex, colIndex2]).Value2.ToString();

                   myArray[myarrayindex, 0] = PartNO;
                   myArray[myarrayindex, 1] = Price;
                   ListViewItem lvi = new ListViewItem();
                   lvi.Text = Convert.ToString(index + 1);
                   lvi.SubItems.Add(PartNO);
                   lvi.SubItems.Add(Price);
                   this.listView1.Items.Add(lvi);

                   myarrayindex++;
                   index++;

               }
           }
           catch (Exception ex)
           {
               app.Quit();

           }
       }
   }

From http://www.developmentnow.com/g/21_2005_9_0_0_592882/Excel-templates-Old-format-
or-invalid-type-library-.ht