<%@ Page Title="" Language="C#" MasterPageFile="~/MasterPage.master" AutoEventWireup="true" CodeFile="Default3.aspx.cs" Inherits="Default3" %>

<%@ Register assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" tagprefix="asp" %>

<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
    <table class="style1">
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
                    DataSourceID="SqlDataSource1">
                    <Columns>
                        <asp:BoundField DataField="cateid" HeaderText="cateid"
                            SortExpression="cateid" />
                        <asp:BoundField DataField="catedesc" HeaderText="catedesc"
                            SortExpression="catedesc" />
                    </Columns>
                </asp:GridView>
                <asp:SqlDataSource ID="SqlDataSource1" runat="server"
                    ConnectionString="<%$ ConnectionStrings:inventory128ConnectionString %>"
                    SelectCommand="SELECT * FROM [category]"></asp:SqlDataSource>
            </td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                <asp:Accordion ID="Accordion1" runat="server" SelectedIndex="0">
                <Panes>
                <asp:AccordionPane runat="server">
                <Header>Address Details</Header>
                <Content>Sr Nagar,Ameerpet,Hyd, AP, 500001</Content>
                </asp:AccordionPane>
                </Panes>
                </asp:Accordion>
                <asp:Accordion ID="AccordionPane" runat="server" SelectedIndex="1">
                <Panes>
                <asp:AccordionPane runat="server">
                <Header>Contact Details</Header>
                <Content>
                <table>
                <tr>
                <td>
                Email :
                </td>
                <td>subrata.badhai@gmail.com</td>
                </tr>
                <tr>
                <td>
                Phone no :
                </td>
                <td>
                8885321552
                </td>
                </tr>
                </table></Content>
                </asp:AccordionPane>
                </Panes>
                </asp:Accordion>
            </td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
        <tr>
            <td>
                &nbsp;</td>
            <td>
                &nbsp;</td>
        </tr>
    </table>
</asp:Content>

ERROR:

Server Error in '/24 nov practice' Application.

Multiple controls with the same ID '_header' were found. FindControl requires that controls have unique IDs.

Description:An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: Multiple controls with the same ID '_header' were found. FindControl requires that controls have unique IDs.

Source Error:

 An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[HttpException (0x80004005): Multiple controls with the same ID '_header' were found. FindControl requires that controls have unique IDs.]
   System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls) +265
   System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls) +311
   System.Web.UI.Control.FillNamedControlsTable(Control namingContainer, ControlCollection controls) +311
   System.Web.UI.Control.FindControl(String id, Int32 pathOffset) +145
   System.Web.UI.Control.FindControl(String id) +12
   System.Web.UI.WebControls.DataBoundControlHelper.FindControl(Control control, String controlID) +81
   System.Web.UI.WebControls.DataBoundControl.GetDataSource() +67
   System.Web.UI.WebControls.DataBoundControl.ConnectToDataSourceView() +159
   System.Web.UI.WebControls.DataBoundControl.OnLoad(EventArgs e) +19
   System.Web.UI.Control.LoadRecursive() +74
   System.Web.UI.Control.LoadRecursive() +146
   System.Web.UI.Control.LoadRecursive() +146
   System.Web.UI.Control.LoadRecursive() +146
   System.Web.UI.Control.LoadRecursive() +146
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2207

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1