VB webform in IronPython asp.net website
The code between <script /> tags is compiled dynamically when the page is first run. This enables you to mix languages. However, the classes in your code-behind files are statically compiled into an assembly by VS.NET ... and a VS.NET project can only support one language at a time.
One solution is to put your VB.NET code-behinds in a separate assembly. For example:

Add a new VB Class Library project to your existing solution


Add a reference to System.Web
Create your VB.NET code-behinds. They should be normal classes inheriting from System.Web.UI.Page.

In your ASP.NET website project, add a reference to the new project
Edit the @ Page directives in your *.aspx files to inherit the classes in the new project


e.g. <%@ Page Inherits="YourNewVBClassLibraryProject.MyVBCodeBehinds" ... /> where the Inherits attribute contains the relevant namespace-qualified class name
I tried to bring a previously done webform made in vb.net to an IronPython asp.net website with no luck. After seeing it didnt work, I tried to write the simplest codebehind vb.net webform to see if there was a problem with vb.net in an IronPython website and I got the following usual error 
"be sure that the defined class in this file matchs with the one in the attribute inherits and that it extends the right base page (page or control)" (sorry if the translation isnt the most accurate I get that message in spanish)
but if I create a vb.net webform in the same website, with the sourcecode in the same file (with the vb.net code between  script runat="server" tags in the same page) I get no problem. 
Do I have to configure something for both kind of sourcecode languages to run in such way in the same IronPython website, like configuring something in the webconfig file or is there some compatibility issue for doing that which can't be resolved?