IIS7.5 Website ​Configurati​on

We're trying to setup two websites, our main site and an application that will load into an iframe in our site.

Our main site is .NET 2.0 and our app is .NET 4.0 we're trying to make our app a child site from the main default however we're getting an error message...

"The value for the 'compilerVersion' attribute in the provider options must be 'v4.0' or later if you are compiling for version 4.0 or later of the .NET Framework. To compile this Web application for version 3.5 or earlier of the .NET Framework"

But we have that all taken care of...is there a way IIS needs to be configured for this?

Is the app pool set to 4.0?

No, the app pool for the site is 2.0....

@Cybermagellan: Make these 2 site be in different Virtual Directory to have them loading in different application pool, or just make them both run in .NET v4.0 if you've tested the v2.0 part will not run into items in the breaking changes list.

Btw, I think I remember someone talking about .Net v4.0 can live with or .NET v2/3 runtimes within the same process?

EDIT: http://blogs.blackmarble.co.uk/blogs/rfennell/archive/2010/03/27/mixed-mode-assembly-is-built-against-version-v2-0-50727-error-using-net-4-development-web-server.aspx

Seems you can add the startup tag contents inside <configuration> section of web.config too.

The hard part is we want to keep 2.0 apps in a 2.0 appPool and 4.0 apps in a 4.0 appPool. Is this something that broke/changed since IIS6 (or even 7.0?) We have multiple sites that are ran kinda mixed like that, but 7.5 (Win Serv 2008 R2) is being a pain.

I found this site...

http://www.aspspider.com/qa/Question4562.aspx

Which talks about taking parts out of the web.config.... wha? Why?

It's not letting you use two different app pools? You should be able to set different pools for both sites, unless the child site isn't a separate application. I'm currently running two sites on 2008 R2. One is in the root under Default Web Site, and the second is a new app "legacy" in the default web site. They're using different app pools just fine.

yeah, ours isn't. It's throwing that compilerVersion error which we just keep going down a rabbit hole on issues

20 hours ago,Cybermagell​an wrote

yeah, ours isn't. It's throwing that compilerVersion error which we just keep going down a rabbit hole on issues

if the main site is running 2.0 then it does not have the compiler version setting.

the child web should have that setting.

is it not in the 4.0 child web's web config ??

a 4.0 web config should be smaller and simpler than a 2.xx config file.

i have some stuff kind of like this and it works but i am not sure if i have the exact case you have.