Question

How can I add custom .ASPX pages to a DotNetNuke site?

Answer 1

Adding any aspx page in dotnetnuke should work ok provided it is inherited from DotNetNuke.Framework.PageBase instead of System.Web.UI.Page. It will work as expected. If you are using an aspx page without code behind use it like this:

<%@ Page Language="C#" Inherits="DotNetNuke.Framework.PageBase" %>

if you are using aspx page with code behind, use it like following:
(vb.net)

Public Class CustomAspnetPage
    DotNetNuke.Framework.PageBase

This applies to any version of dotnetnuke.