running asp.net 2.0 and 1.1 on same site…works in one area but crashes another

Question

Our site is running ASP.NET 1.1, and I need to have ASP.NET 2.0 running in a separate section to the same site until we get it fully converted over. I created the new folder and in IIS, I ‘create application’ process on the folder. Then, I went to the ASP.NET tab and changed the version for my new app to 2.0. This works fine on my local computer and works fine for the admin folder that achieves the same task which a co-worker created, but for this folder, it made the .NET 1.1 parts of the site crash giving the following error message (below). I ‘removed application’ on my new folder and it fixed the error.

=====================================
Server Application Unavailable 
The web application you are attempting to access on this web server is
currently unavailable.  Please hit the "Refresh" button in your web
browser to retry your request. 
=====================================

Answer 1

Your problem is with the application pools you are adding your applications to. .NET 1.1 and .NET 2.0 can not run side by side in the same AppPool. (They certainly can't run in the same folder or virtual directory).

The easiest way to handle this is to create an AppPool called .NET 1.1 and one called .NET 2.0.

When you run 'create application', make sure you select the correct AppPool for the .NET version the application uses.

That should take care of any errors when you run your application.

Answer 2

You can't run two different versions of ASP.NET in the same application pool. You will need two separate application pools and two separate websites to serve up ASP.NET 1.1 and ASP.NET 2.0 from the same IIS installation.