我正在使用VS2010，C＃，ASP.NET，我已经插入了Ajax Control Toolkit Tab容器，它工作得很好但是当我在另一个面板上插入一个模态弹出扩展器时，标签不会显示！这里出了什么问题？
请帮帮我
为什么会发生......？
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" AjaxFrameworkMode="Enabled" runat="server">
</asp:ScriptManager>
＆lt;％ - - ％＆gt; ＆lt;％ - - ％＆gt;
<asp:Button ID="btnIndexDel" runat="server" Text="Button" Style="display: none" />
<asp:Button ID="BtnFstModelPopUp" runat="server" Text="Button" Style="display: none" />
<b style="color: #4E555D">
<asp:Literal ID="Literal19" runat='server' Text='<%$ Resources:Resource,tools %>'></asp:Literal>/</b>
<b style="color: #20729F;">
<asp:Literal ID="Literal1" runat='server' Text='HotFolder Configuration'></asp:Literal></b><hr />
<div>
<br />
<center>
<table id="maintable" height="530px" width="1000px" horizontalalign="center" bordercolor="gainsboro"
bgcolor="white" style="border-bottom-width: 1px; border-bottom-style: solid;
border-top-width: 1px; border-top-style: solid; border-left-width: 1px; border-left-style: solid;
border-right-width: 1px; border-right-style: solid; border-bottom-color: #8C8B83;
border-top-color: #8C8B83; border-left-color: #8C8B83; border-right-color: #8C8B83;">
<tr valign="top">
<td colspan="5" bgcolor="#E5E5E5" height="20" class="topnav" style="font-size: 10px;
font-family: verdana">
<font style="color: #000000"><strong>
<asp:Literal ID="Literal2" runat='server' Text='HotFolder Configuration'></asp:Literal>
</strong></font>
</td>
</tr>
<tr>
<td>
<asp:Panel ID="pnl3" runat="server" Height="536px" Width="100%">
<div>
<asp:UpdatePanel runat="server" ID="updpnl">
<ContentTemplate>
<cc1:TabContainer runat="server" ID="HFtabContainer" ActiveTabIndex="2" Width="100%"
Height="476px" CssClass="fancy fancy-green" AutoPostBack="true"><cc1:TabPanel ID="HFConfig" runat="server"><HeaderTemplate>HF Configuration</HeaderTemplate><ContentTemplate><center><br /><br /><br /><asp:Panel ID="pnlhfconfig" runat="server" Height="100%" Width="100%"><table bordercolor="gainsboro" bgcolor="white" style="border-bottom-width: 1px; border-bottom-style: solid;
border-top-width: 1px; border-top-style: solid; border-left-width: 1px; border-left-style: solid;
border-right-width: 1px; border-right-style: solid; border-bottom-color: #8C8B83;
border-top-color: #8C8B83; border-left-color: #8C8B83; border-right-color: #8C8B83;"
id="TABLE2" language="javascript"><tbody><tr><td colspan="3" bgcolor="#E5E5E5" height="20" class="topnav" style="font-size: 10px;
font-family: verdana"><font style="color: #000000"><strong><asp:Literal ID="Literal4" runat='server' Text='HF Configuration'></asp:Literal>  </strong></font> </td></tr><tr><td><asp:Label ID="lbluncheader" runat="server" Text='HotFolder UNCHeader'></asp:Label></td><td><asp:TextBox ID="txthfuncheader" runat="server" MaxLength="50" Style="z-index: 102;"
Width="250px"></asp:TextBox><asp:RequiredFieldValidator ID="rfvuncheader" runat="server"
ErrorMessage="UNCHeader is required." ControlToValidate="txthfuncheader" Display="None"
ValidationGroup="save"></asp:RequiredFieldValidator></td><td><asp:Label ID="Label1" runat="server" Font-Bold="True" ForeColor="Red" Text="*"></asp:Label></td></tr><tr><td><asp:Label ID="lblrootfolder" runat="server" Text='Hot RootFolder'></asp:Label></td><td><asp:TextBox ID="txtrootfolder" runat="server" MaxLength="50" Width="250px"></asp:TextBox><asp:RequiredFieldValidator
ID="rfvUNH" runat="server" ErrorMessage="RootFolder is required." ControlToValidate="txtrootfolder"
Display="None" ValidationGroup="save"></asp:RequiredFieldValidator></td><td><asp:Label ID="Label2" runat="server" Font-Bold="True" ForeColor="Red" Text="*"></asp:Label></td></tr><tr><td colspan="2" align="center"><table><tr><td><asp:Button ID="btnsave" runat="server" Text='Save' Width="55px" BackColor="#E5E5E5"
ForeColor="Black" ValidationGroup="save" /></td><td><asp:Button ID="btncancel" runat="server" Text='Cancel' Width="55px" BackColor="#E5E5E5"
ForeColor="Black" /></td></tr><tr><td><asp:ValidationSummary ID="ValidationSummary1" runat="server" ShowMessageBox="True"
ShowSummary="False" ValidationGroup="save" /></td></tr></table></td></tr></tbody></table></asp:Panel></center></ContentTemplate></cc1:TabPanel><cc1:TabPanel ID="tabpnlhfindexmaster" runat="server" HeaderText="HF IndexMaster"><HeaderTemplate>HF IndexMaster</HeaderTemplate><ContentTemplate><div><table><tr><td>   </td></tr><tr><td><asp:Repeater ID="Repeater2" runat="server"><ItemTemplate><asp:LinkButton ID="LnkPath" runat="server"></asp:LinkButton></ItemTemplate></asp:Repeater></td></tr><tr><td><ul id="dashboard-buttons"><asp:Repeater ID="Repeater1" runat="server"><ItemTemplate><li><asp:LinkButton ID="context" runat="server" CssClass="folder" oncontextmenu="javascript:return GetText(this,event);" /></li></ItemTemplate></asp:Repeater></ul></td></tr><tr><td><asp:LinkButton ID="lnkPrevious" runat="server" Font-Bold="true" Visible="false"
ForeColor="#FF3399" Text="<%$ Resources:Resource,prev %>"></asp:LinkButton>  <asp:LinkButton
ID="lnkNext" runat="server" Font-Bold="true" Visible="false" ForeColor="#FF3399"
Text="<%$ Resources:Resource,next %>"></asp:LinkButton></td></tr></table></div></ContentTemplate></cc1:TabPanel><cc1:TabPanel ID="hfuserfiletypes" runat="server"><HeaderTemplate>HF User FileTypes</HeaderTemplate><ContentTemplate><center><asp:Table ID="Table1" runat="server" Height="392px" BorderColor="gainsboro" bgcolor="white"
Style="border-bottom-width: 1px; border-bottom-style: solid; border-top-width: 1px;
border-top-style: solid; border-left-width: 1px; border-left-style: solid; border-right-width: 1px;
border-right-style: solid; border-bottom-color: #8C8B83; border-top-color: #8C8B83;
border-left-color: #8C8B83; border-right-color: #8C8B83;"><asp:TableRow ID="TableRow2" runat="server"><asp:TableCell colSpan="5" bgColor="#E5E5E5" Height="20" class="topnav" Style="font-size: 10px;
font-family: verdana">
<font style="color: #000000"><strong>
<asp:Literal ID="Literal3" runat='server' Text='HF User FileType'></asp:Literal></strong></font>
</asp:TableCell></asp:TableRow><asp:TableRow ID="TableRow1" runat="server"><asp:TableCell>
<asp:Table ID="lefttable" runat="server" Height="376px" Width="365px">
<asp:TableRow>
<asp:TableCell>
<asp:Table ID="useridtable" runat="server" Height="32px" Width="241px" HorizontalAlign="Center">
<asp:TableRow>
<asp:TableCell>
<asp:Label ID="lbluserid" runat="server" meta:resourceKey="lbluserid" Text="User Id"></asp:Label>
</asp:TableCell>
<asp:TableCell>
<asp:DropDownList ID="lstUserId" runat="server" Width="128px" AutoPostBack="True">
</asp:DropDownList>
<asp:Label ID="lblman" runat="server" ForeColor="Red" Text="*"></asp:Label>
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow>
<asp:TableCell>
<asp:Table ID="treetable" runat="server" Height="265px" Width="243px" HorizontalAlign="center">
<asp:TableRow>
<asp:TableCell HorizontalAlign="LEFT">
<asp:Panel ID="Panel1" runat="server" Height="324px" Width="241px" BorderStyle="Inset"
BorderWidth="1px" BorderColor="#8C8B83" ScrollBars="Auto">
<asp:TreeView ID="tvusers" runat="server" Height="247px" PathSeparator="\" ShowCheckBoxes="All"
ShowLines="True" NodeStyle-ForeColor="black" ExpandDepth="0">
</asp:TreeView>
</asp:Panel>
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow>
<asp:TableCell>
<asp:Table ID="buttonstable" runat="server" Height="31px" Width="241px" HorizontalAlign="center">
<asp:TableRow>
<asp:TableCell>
<asp:Button ID="btnok" runat="server" meta:resourceKey="btnok" Text="Ok" Width="60px"
BackColor="#E5E5E5" ForeColor="Black" />
<asp:Button ID="Button1" runat="server" meta:resourceKey="btnCancel" Text="Cancel"
Width="60px" BackColor="#E5E5E5" ForeColor="Black" />
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</asp:TableCell></asp:TableRow></asp:Table></center></ContentTemplate></cc1:TabPanel></cc1:TabContainer>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</asp:Panel>
</td>
</tr>
</table>
</center>
</div>
<br />
<br />
<div>
</div>
<div>
<center>
<asp:Panel ID="PnlFstModelPopUp" runat="server" BackColor="White" CssClass="modalPopup"
Width="550px" Style="display: none">
<b style="color: #20729F;">
<asp:Literal ID="Literal5" runat='server' Text='<%$ Resources:Resource,indexcreation %>'></asp:Literal></b>
<span style="float: right; vertical-align: top;">
<asp:ImageButton ID="ImageButton1" runat="server" ImageUrl="~/assets/icons/close.png"
Width="20px" Height="20px" />
</span>
<hr />
<table border="0" cellpadding="" cellspacing="">
<tr align="center">
<td>
<asp:Label ID="Label3" runat="server" Text="<%$ Resources:Resource,indexid %>"></asp:Label>
</td>
<td>
<asp:TextBox ID="txtIndexID" runat="server" MaxLength="25"></asp:TextBox>
<asp:Label ID="Label4" runat="server" ForeColor="Red" Text="*"></asp:Label>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="Index ID is required."
ControlToValidate="txtIndexID" Display="None" ValidationGroup="IndexProp"></asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="revIndexID1" runat="server" Display="None" ControlToValidate="txtIndexID"
ValidationExpression=".{3}.*" ErrorMessage="Minimum 3 characters." ValidationGroup="IndexProp"></asp:RegularExpressionValidator>
<asp:RegularExpressionValidator ID="revIndexID2" runat="server" ControlToValidate="txtIndexID"
Display="None" ValidationExpression="^[a-zA-Z0-9\s_@.-]*$" ErrorMessage="Special characters not allowed."
ValidationGroup="IndexProp"></asp:RegularExpressionValidator>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label5" runat="server" Text="<%$ Resources:Resource,desc %>"></asp:Label>
</td>
<td>
<asp:TextBox ID="txtDesc" runat="server"></asp:TextBox>
</td>
</tr>
<tr align="center">
<td colspan="2">
<asp:Button ID="btnproceed" runat="server" Text="<%$ Resources:Resource,proceed %>"
ValidationGroup="IndexProp" />
<%--<asp:Button ID="btncancel" runat="server" Text="Cancel" />--%>
</td>
</tr>
</table>
</asp:Panel>
</center>
</div>
<cc1:ModalPopupExtender ID="FstModelPopUp" runat="server" TargetControlID="BtnFstModelPopUp"
PopupControlID="PnlFstModelPopUp" Drag="true" DropShadow="true" BackgroundCssClass="modalBackground"
CancelControlID="btncancel" ></cc1:ModalPopupExtender>
</form>