Grid disappears while editing Radgrid

<telerik:RadGrid ID="RadGrid1" runat="server" OnNeedDataSource="RadGrid1_NeedDataSource"
    AllowPaging="true" OnUpdateCommand="RadGrid1_UpdateCommand" OnInsertCommand="RadGrid1_InsertCommand"
    OnDeleteCommand="RadGrid1_DeleteCommand" >   
    <MasterTableView AutoGenerateColumns="False" DataKeyNames="OrderID" CommandItemDisplay="Top">
        <Columns>
           <%--Your Columns here--%>
        </Columns>
    </MasterTableView>
</telerik:RadGrid>

protected void RadGrid1_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
        {
            SqlConnection conn = new SqlConnection("Provide your Connectionstring here");
            DataTable dt1 = new DataTable();
            //Put Your code to load the data
            string strquery = "SELECT [OrderID], [CustomerID], [EmployeeID], [OrderDate], [ShipName] FROM [Orders]";
            SqlDataAdapter adapter1 = new SqlDataAdapter(strquery, conn);
            conn.Open();
            adapter1.Fill(dt1);
            conn.Close();
            RadGrid1.DataSource = dt1;
        }

Thanks,
A2H
My Blog