Unrecognized element 'folderLevelBuildProviders'?

I opened atomesite using Visual studio , I modified MVC 1 to MVC 2, build succeceed, but the web page is giving me this error, I tried aspnet_regiis –iru but tdidnt work?

Server Error in '/' Application.
    Configuration Error
    Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.

    Parser Error Message: Unrecognized element 'folderLevelBuildProviders'.

    Sour开发者_高级运维ce Error:

    Line 348:                <codeSubDirectories />
    Line 349:                <expressionBuilders />
    Line 350:                <folderLevelBuildProviders />
    Line 351:            </compilation>
    Line 352:            <pages>


    Source File: C:\Windows\Microsoft.NET\Framework\v2.0.50727\Config\web.config    Line: 350 

Not sure if this applies to MVC, but this fixed the same error for me with Web Forms:

http://forums.asp.net/t/1620379.aspx/1

Make sure you have followed all the 9 steps of the migration guide.

Change your application pool to be running on .NET 4.0.

This worked for me.