Lock Screen on my email sending page asp.net

i have a page wherein i need to lock the screen when user clicks on the send email button, but everything is happening except i am unable to see my lock screen page. i have used the update progress for this purpose.. m posting part of the code here .aspx part

<asp:UpdatePanel ID="SendMailUpdatePanel" runat="server">
    <ContentTemplate>
        <div style="float: right;">
            <asp:Button ID="btnSend" runat="server" Text="Send" ToolTip="Send "
                Visible="false" Font-Bold="True" OnClick="btnSendResume_Click" />                          
            <asp:Button ID="btnDown" runat="server" Text="Download IDs" ToolTip="follow-up"
                Visible="false" Font-Bold="True" OnClick="btnDownloadEmailIDs_Click" />
        </div>
    </ContentTemplate>
</asp:UpdatePanel>
    <table>
        <td style="width: auto; vertical-align: top;">开发者_StackOverflow社区
            <asp:UpdateProgress ID="UpdateProgress2" runat="server" AssociatedUpdatePanelID="SendMailUpdatePanel">
                <ProgressTemplate>
                    <div id="blur" style="width: 100%; background-color: black; moz-opacity: 0.5; khtml-opacity: .5;
                        opacity: .5; filter: alpha(opacity=50); z-index: 120; height: 100%; position: absolute;
                        top: 0; left: 0;">
                        <div id="progress" style="z-index: 200; background-color: White; position: absolute; top: 0pt;
                            left: 0pt; border: solid 1px black; padding: 5px 5px 5px 5px; text-align: center;">
                            <b>Mail in progress.Please Wait...</b>
                            <br />
                        </div>
                    </div>
                </ProgressTemplate>
            </asp:UpdateProgress>
        </td>
    </table>

.cs part

protected void btnSendResume_Click(object sender, EventArgs e)
        {
            System.Threading.Thread.Sleep(2000);

}

rest of the part i have not mentioned here...any help

Your HTML Table is incorrectly formed. You have no <tr> elements, but the real problem probably lies with your style attributes, please see my updated code below.

You can find a good example of how to accomplish what you are trying to do here: http://blogs.visoftinc.com/2008/03/13/Modal-UpdateProgress-for-UpdatePanel-Revisited/

Try adjusting your code to the following:

<asp:UpdatePanel ID="SendMailUpdatePanel" runat="server">
    <ContentTemplate>
        <div style="float: right;">
            <asp:Button ID="btnSend" runat="server" Text="Send" ToolTip="Send "
                Visible="false" Font-Bold="True" OnClick="btnSendResume_Click" />                          
            <asp:Button ID="btnDown" runat="server" Text="Download IDs" ToolTip="follow-up"
                Visible="false" Font-Bold="True" OnClick="btnDownloadEmailIDs_Click" />
        </div>
    </ContentTemplate>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress2" runat="server" AssociatedUpdatePanelID="SendMailUpdatePanel">
    <ProgressTemplate>
        <div id="blur" style="position:fixed; top:0px; bottom:0px; left:0px; right:0px; overflow:hidden; padding:0; margin:0; background-color:black; filter:alpha(opacity=50); opacity:0.5; z-index:1000;" />
        <div id="progress" style="position:fixed; top:30%; left:43%; width:14%; z-index:1001; background-color:white; border:solid 1px black; padding:5px; text-align:center;">
            <b>Mail in progress.Please Wait...</b>
            <br />
            <br />
        </div>
    </ProgressTemplate>
</asp:UpdateProgress>