IIS 6 Virtual directory MVC not working but Subdomain is

Question

I get the following error when using MVC as a virtual directory

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, remove the 'targetFramework' attribute from the element of the Web.config file.

at url blah.domain.com/MVC

but at blahmvc.domain.com

I get exactly what i want.

so i figured it was a configuration problem so I deleted the virtual directory clicked on blahmvc.domain.com and 'Save configuration to a File...'

and then on
blah.domain.com
new virtual directory from file
Read File
Location
Create A new virtual directory
Alias : MVC
and I get the same error when I try and go to the page

Using IIS6 and .NET 4.0.21006

Answer 1

Try remove targetFramework parameter in system.web/compilation section of the web.config file. This worked for me.

Answer 2

The problem seems to have been slightly different versions of runtimes (betas RC's etc)