ASP gives this error message: Both DataSource and DataSourceID are defined on 'profileGridView'. Remove one definition

<code>
    <asp:Content ID="manageProfileContent" runat="server" ContentPlaceHolderID="mainContentPlaceHolder">
    <div class="Menu">
       <asp:Label ID="manageProfileTitle" runat="server" Text="Manage Profile" />
    </div>            
    <br />
    <asp:Panel ID="manageProfileMessagePanel" runat="server">
        <asp:Label ID="manageProfileMessageLabel" runat="server" Font-Names="Sans-serif" Font-Size="Medium" Font-Bold="true" ForeColor="Red" Text="" />
    </asp:Panel>
    <br />
    <asp:GridView ID="profileGridView" runat="server" AutoGenerateColumns="False" 
        BackColor="White" Border开发者_开发技巧Color="#999999" BorderStyle="Solid" BorderWidth="1px" 
        CellPadding="3" ForeColor="Black" GridLines="Vertical" 
    DataKeyNames="userid" DataSourceID="profileGridViewSqlDataSource">
        <FooterStyle BackColor="#CCCCCC" />
        <PagerStyle BackColor="#999999" ForeColor="Black" HorizontalAlign="Center" />
        <SelectedRowStyle BackColor="#000099" Font-Bold="True" ForeColor="White" />
        <HeaderStyle BackColor="Black" Font-Bold="True" ForeColor="White" />
        <AlternatingRowStyle BackColor="#CCCCCC" />
        <Columns>
            <asp:BoundField DataField="userid" HeaderText="userid" ReadOnly="True" 
                SortExpression="userid" />
            <asp:CheckBoxField DataField="administrator" HeaderText="administrator" 
                SortExpression="administrator" />
            <asp:CheckBoxField DataField="policy_originator" HeaderText="policy_originator" 
                SortExpression="policy_originator" />
            <asp:CheckBoxField DataField="policy_approver" HeaderText="policy_approver" 
                SortExpression="policy_approver" />
            <asp:CheckBoxField DataField="employee"  HeaderText="employee" 
                SortExpression="employee" />
        </Columns>        
        </asp:GridView>
    <asp:SqlDataSource ID="profileGridViewSqlDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:policymgmConnectionString %>" 

        SelectCommand="SELECT [userid], [administrator], [policy_originator], [policy_approver], [employee] FROM [tbl_profile]">
    </asp:SqlDataSource>
</asp:Content>
</code>

Do not specify profileGridView.Datasource = datatable; profileGridView.DataBind(); when you have already specified datasourceid for the gridview. As the error clearly says, either remove datasourceid for the gridview or the lines profileGridView.Datasource = datatable; profileGridView.DataBind(); from your code!