各位大哥！TreeView的问题 要跪了我！！！

树：  <iewc:TreeView ID="tv2" SelectedStyle="color:#e8f4ff" runat="server" Width="190px"
   Height="100%" BorderColor="White" SystemImagesPath="../../../webctrl_client/1_0/treeimages/"
   SelectExpands="True"BorderWidth="0px">                                                                     
        <iewc:TreeNode  Text="资产信息" Expanded="True">
            <iewc:TreeNode NavigateUrl="../../MRR_networkDevice/networkDevice_Index.aspx"   
            Text="网络设备" Expanded="True" Target="MMR_main" >
            </iewc:TreeNode>     
                                                               
            <iewc:TreeNode Text="服务器设备" Expanded="True"  
             NavigateUrl="../../MMR_serverDevice/serverDevice.aspx"  Target="MMR_main">
            </iewc:TreeNode>
                                                                 
            <iewc:TreeNode NavigateUrl="../../MMR_SafetyDevice/SafetyDevice_Index.aspx"  
            Text="信息安全设备" Expanded="True" Target="MMR_main">
            </iewc:TreeNode>
                                                                    
            <iewc:TreeNode NavigateUrl="../../MMR_AppSystemDevice/AppSystemDevice_Index.aspx"  
             Text="应用系统" Expanded="True" Target="MMR_main">
            </iewc:TreeNode>
                                                                    
            <iewc:TreeNode NavigateUrl="../MMR_baseDevice/baseDevice.aspx" 
             Text="基础设施" Expanded="True" Target="MMR_main">
            </iewc:TreeNode>
                                                                    
            <iewc:TreeNode NavigateUrl="../../MMR_OtherDevice/OtherDevice_Index.aspx"  
             Text="其他" Expanded="True" Target="MMR_main">
            </iewc:TreeNode>
         </iewc:TreeNode>
         ··········（省略后面一个意思）
 </iewc:TreeView>框架：
<frameset  cols="178,10,*" rows="*" border="0" framespacing="0" frameborder="0"  id="thisFrame" >
<frameset>
<frame name="LeftFrame" src="_left_top.aspx" frameborder="0" border="0" framespacing="0" >
<frame name="middleframe" src='t_1.htm' scrolling='no' frameborder='NO' >
<frame id="MMR_main" src="_main.aspx"  scrolling="auto" 
                 frameborder="0" border="0"framespacing="0">
<noframes>
<body bgcolor="#FFFFFF">
  <table width="100" border="4" align="left" cellpadding="10" cellspacing="2" height="100%">
     <tr>
 <td>
                           <p align="center">
                                <font color="#0000FF">浏览器功能支持限制</font>
                           </p>
   <p>&nbsp&nbsp&nbsp&nbsp非常抱歉，您的浏览器不支持框架模式，
                              无法使用本模块，请使用支持框架的浏览器。
                           </p>
   <p>
                                 <font color="#FF0000">*</font> 
                                 <font color="#000099">建议使用 Internet Explorer 6.0 
         或版本更高的浏览器使用本模块。
                                 </font>
                            </p>
  </td>
     </tr>
         </table>
</body>
</noframes>
</frameset>
</frameset>
                                                                 
问题 红色部分的有问题么？为毛我单击节点的时候 会弹出一个新的窗口！！！！跪求解释啊~怎么能不弹新窗口了！！！