IIS error - HTTP Error 500.24 - Internal Server Error

I recently installed IIS on my Windows 7 PC and when i opened http://localhost/ it showed

********************ERROR**********************  
HTTP Error 500.24 - Internal Server Error
An ASP.NET setting has been detected that does not apply in Integrated managed pipeline mode.  
********************ERROR**********************

********************Detailed Error Information**************  
Module:  ConfigurationValidationModule  
Notification:  BeginRequest  
Handler:  StaticFile  
Error Code:  0x80070032  
Requested URL  :http://localhost:80/  
Physical Path  :C:\inetpub\wwwroot  
Logon Method  :Not yet determined  
Logon User  :Not yet determined  
************************

I'm not sure what code/configurations you're running, but you may have to change the App Pool for your site to use Classic instead of Integrated mode.

• Here's a good explanation of the difference.

Classic mode is where IIS only works with ISAPI extensions and ISAPI filters directly ... Integrated mode handles all requests through a unified pipeline for IIS and is tightly integrated with ASP.NET through that same pipeline.

• And where you could be running into trouble:

Some legacy code may require that you run in classic mode to execute without error. To take full advantage of IIS we strongly encourage you to review your code if your application throws an error in Integrated but runs fine in Classic.

• Laundry list of issues to debug Integrated mode.