Datalist not appearing EditItemTemplate | The network path was not found

Server Error in '/' Application.

The network path was not found

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.ComponentModel.Win32Exception: The network path was not found

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.

HTML Records

                        </ProgressTemplate>
                    </asp:UpdateProgress>


                                     </tr>

                                </table>


                    </EditItemTemplate>

                </asp:DataList>

                <asp:HiddenField ID="UN" runat="server" />

                <asp:SqlDataSource runat="server" ID="SqlDataSource2" ConnectionString='<%$ ConnectionStrings:db_dogalinaConnectionString %>' SelectCommand="SELECT * FROM [UserDetail] WHERE ([UserName] = @UserName)">
                    <SelectParameters>
                        <asp:ControlParameter ControlID="UN" PropertyName="Value" DefaultValue="" Name="UserName" Type="String"></asp:ControlParameter>

                    </SelectParameters>
                </asp:SqlDataSource>

Code Behind CS

protected void dataEditProfile_ItemCommand(object source, DataListCommandEventArgs e)
    {
        switch (e.CommandName)
        {
            case "Edit":
                {
                    dataEditProfile.EditItemIndex = e.Item.ItemIndex;
                    dataEditProfile.DataBind();


                }break;

            case "Update":
                {`
                    BilgileriDoldur();
                    DL.Lib.ormDataContex...`

void Some Record

private void BilgileriDoldur()
    {
        UserName = HttpContext.Current.User.Identity.Name;
        DL.Lib.ormDataContext db = new Lib.ormDataContext();
        SelectedUser = db.UserDetails.First(a => a.UserName == UserName);
        UN.Value = SelectedUser.UserName;


    }

Web.Config ConnectionStrings

<connectionStrings>
<clear/>
<add name="dbConnectionString" connectionString="Server=mssql.******.com; Database=******; User Id=******; Password=******" providerName="System.Data.SqlClient"/>
<add name="LocalSqlServer" connectionString="Server=mssql.******.com; Database=******; User Id=admindb; Password=******" providerName="System.Data.SqlClient"/>
<add name="db_dogalinaConnectionString" connectionString="Server=mssql.******.com; Database=******; User Id=******; Password=******" providerName="System.Data.SqlClient"/></connectionStrings>