the file could not be loaded into the web forms designer

samir25 used Ask the Experts™
i am openign a project and on click ign to a file (aspx file ) i get this error

the file could not be loaded into the web forms designer. please correct the following error and then try laoding it again:
Type Abstract

make sure all of the classes used in the page are built or referenced in the help for more info

can someone please please suggest what can i do to resolve ths..

thanks a lto
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can you post the aspx and aspx.cs / aspx.vb so we can have a look?

I would say you are referencing a .net dll or project in your page that is not been included in your project.

if you are using the reference should be underlined. you'll have to add this reference


check the HTML in the HTML Designer and make sure that it doesnt has invalid entries.

HTH, Nauman.
If your page inherits from abstract class instead of System.Web.UI.Page class, or not abstact class inherited from Page, designer will not be able to load it.
You have 2 option:
Make your page parent class not abstract.
OR every time you need to open page in designer replace parent class of your page back to default System.Web.UI.Page, make your changes in designer and change it back to your parent class before compilation.


this is a part of the big code...
this is .vb one
Imports System.IO
Imports DotNetNuke.Entities.Tabs
Imports DotNetNuke.UI.Skins

Namespace DotNetNuke.Framework
      ''' -----------------------------------------------------------------------------
    Public Class CDefault

        Inherits DotNetNuke.Framework.PageBase

        Public Comment As String = ""
        Public Title As String = ""
        Public Description As String = ""
        Public KeyWords As String = ""
        Public Copyright As String = ""
        Public Generator As String = ""
        Public Author As String = ""

        Protected ScrollTop As System.Web.UI.HtmlControls.HtmlInputHidden
        Protected SkinError As System.Web.UI.WebControls.Label
        Protected SkinPlaceHolder As System.Web.UI.WebControls.PlaceHolder

        Protected CSS As System.Web.UI.WebControls.PlaceHolder
        Protected FAVICON As System.Web.UI.WebControls.PlaceHolder

#Region " Web Form Designer Generated Code "

        'This call is required by the Web Form Designer.
        <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

        End Sub

#End Region

        ''' -----------------------------------------------------------------------------
        Public Property PageScrollTop() As Integer
                If ScrollTop.Value.Length > 0 AndAlso IsNumeric(ScrollTop.Value) Then
                    Return CInt(ScrollTop.Value)
                End If

and this is the aspx starting part..
<%@ Page CodeBehind="Default.aspx.vb" language="vb" AutoEventWireup="false" Explicit="True" Inherits="DotNetNuke.Framework.CDefault" %>
<%@ Register TagPrefix="dnn"  Namespace="DotNetNuke.Common.Controls" Assembly="DotNetNuke" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
      <HEAD id="Head">
                  <%= Title %>

what is missing in it and what do i need to do?
pls explain

thanks a lot for reposnding

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