你是怎么设置的物理路径到您的网站？

What did you set your physical path to your website?

在IIS管理器右侧有基本设置在这里你能看到它的指向。

On the right hand side in IIS Manager there is 'Basic Settings' where you can see where its pointing.

您已经检查之后，确认为您的网站的应用程序池是框架V4.0。再在IIS管理器下看应用程序池，找到您的网站，并确保该框架的版本是4.0（集成）

After you've checked that, make sure the application pool for your website is for v4.0 of the framework. Again in the IIS Manager look under Application Pools, find your website and ensure the framework version is 4.0 (Integrated)