100分 :服务器是WINDOWS SERVER 2008的,在怎么使用索引服务 查询文件

100分求助 :服务器是WINDOWS SERVER 2008的,在如何使用索引服务 查询文件
服务器是08的,http://support.microsoft.com/kb/820983介绍了如何使用索引服务编程查找文件,我就是按照上面坐的,只不过把索引服务目录的名称修改成我的ShareFiles,前端代码是:
C# code
<%@ Page Language="C#" CodeBehind="Default.aspx.cs" AutoEventWireup="false" Inherits="IndexService08._Default" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<html>
   <head>
      <title>WebForm3</title>
      <meta name="GENERATOR"  content ="Microsoft Visual Studio 7.0">
      <meta name="CODE_LANGUAGE"  content ="C#">
      <meta name="vs_defaultClientScript" content="JavaScript">
      <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
   </head>
   <body MS_POSITIONING="GridLayout">
      <form id="WebForm3" method="post" runat="server">
         <asp:DataGrid id="DataGrid1" 
             style=" z-index : 102;  left : 326px;  position : absolute;  top : 141px; width:auto;" 
             runat="server"></asp:DataGrid>
         <asp:Button id="Button1" 
             style=" z-index : 103;  left : 92px;  position : absolute;  top : 199px; right: 806px;" 
             runat="server" Text="Button" onclick="Button1_Click"></asp:Button>
         <asp:TextBox id="TextBox1" style=" z-index : 101;  left : 90px;  position : absolute;  top : 136px" runat="server"></asp:TextBox>
         <asp:Label ID="Label1" runat="server" Text=""></asp:Label>
         <p>
         <asp:GridView ID="GridView1" runat="server" style=" z-index : 103;  left : 92px;  position : absolute;  top : 280px; right: 806px; width:auto " 
             runat="server">
         </asp:GridView>
         </p>
         <asp:TextBox ID="txtPath" runat="server"></asp:TextBox>
      </form>
   </body>
</html>


后台代码:
C# code

  using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;

namespace IndexService08
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            string strCatalog = "ShareFiles";//"TestCatalog";
            string strQuery = "";

            strQuery = "Select Filename,Size,Directory,Write,Path from Scope()  where FREETEXT('" + TextBox1.Text + "')";
            string connstring = "Provider=MSIDXS.1;Integrated Security .='';Data Source=" + strCatalog;

         System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection(connstring);
            conn.Open();

            System.Data.OleDb.OleDbDataAdapter cmd = new System.Data.OleDb.OleDbDataAdapter(strQuery, conn);

            System.Data.DataSet testDataSet = new System.Data.DataSet();

            cmd.Fill(testDataSet, "SearchResults");
            DataView source = new DataView(testDataSet.Tables[0]);
            //DataGrid1.DataSource = source;
            //DataGrid1.DataBind();
            this.GridView1.DataSource = source;
            this.GridView1.DataBind();
            conn.Close();
            this.Label1.Text = "共有"+testDataSet.Tables[0].Rows.Count +"条记录";
        }
    }
}

能实现索引服务,但是我想在索引目录的下一级文件夹查找,如果我的索引目录映射的文件夹是E盘中的所有文件和所有文件夹,但是我想在E盘中的某个字文件夹中索引文件,如何实现,谢谢,我觉得可能是在链接语句那个地方设置,但是不知怎么设置,请高人指点,谢谢