HTTP Error 404.3 - Not Found The page you are requesting cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a MIME map.

While I was hosting ASP website in iis7 I got the following error message. These are the steps I followed to solve the error

HTTP Error 404.3 - Not Found The page you are requesting cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a MIME map.
You just open control panel as shown below:

In the control panel you open “Turn windows features on or off” section as below:

Just refresh the page after finishing the above steps.