Unable to convert Excel work sheet to Datatable in Windows 2003

static System.Data.DataTable lFnConvertWorkSheetToDatatblae(string lStrFileName, string aStrWorkSheetName)
       {

           string lStrConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + lStrFileName + ";Extended Properties=Excel 8.0;";

           OleDbConnection lObjConn = null;
           OleDbDataAdapter lObjSheetAdapter = null;

           try
           {
               System.Data.DataTable lDTSheetData = new System.Data.DataTable();

               using (lObjConn = new OleDbConnection(lStrConnectionString))
               {
                   lObjConn.Open();

                   lObjSheetAdapter = new OleDbDataAdapter("select * from [" + aStrWorkSheetName + "$]", lObjConn);

                   lObjSheetAdapter.Fill(lDTSheetData);

               }

               return lDTSheetData;
           }
           catch (Exception)
           {
               return null;
           }
           finally
           {

               if (lObjSheetAdapter != null)
               {
                   lObjConn.Close();
                   lObjSheetAdapter.Dispose();
               }

               if (lObjConn != null)
               {
                   lObjConn.Dispose();
               }

           }
       }