I am trying to get a local install of DotNetNuke 6.2.2 on my Windows 7 SP1 x64 computer. Here is the process I followed;

1. Install Visual Studio Express 2012 (this gave me SQL Server Express 2012)
2. Install IIS7.5 using Control Panel-->Programs-->Turn Windows Features on/Off
3. Download the Install package for DNN 6.2.2.
4. Right-click on the downloaded zip file and select Properties-->Unblock
5. I unzipped the files into c:\inetpub\wwwroot\dnn
6. I assigned modify rights for the IIS App Pool\DefaultAppPool account to c:\inetpub\wwwroot\dnn
7. I launched IIS Manager and created an application below Default Web Site called DNN and mapped the path to the c:\inetpub\wwwroot\dnn location.

When I run http://localhost/dnn I get the following error. Any ideas?

HTTP Error 500.19 - Internal Server Error

The requested page cannot be accessed because the related configuration data for the page is invalid.

Module	IIS Web Core
Notification	BeginRequest
Handler	Not yet determined
Error Code	0x80070021
Config Error	This configuration section cannot be used at this path. This happens when the section is locked at a parent level. Locking is either by default (overrideModeDefault="Deny"), or set explicitly by a location tag with overrideMode="Deny" or the legacy allowOverride="false".
Config File	\\?\C:\inetpub\wwwroot\DNN\web.config

OK, I found the main problem - When I installed IIS7.5 using Control Panel-->Programs-->Turn Windows Features on/Off, I did not select the ASP components. After I did that, everything worked OK. However, I like the idea of creating a host name in the local computer host file and creating a separate web site with a separate app pool. I will do that. Thanks for the help.

I had the same error using Windows 10, IIS 10 and after installing DNN 8.0.0. The fix that worked for me was: Control Panel-->Programs-->Turn Windows Features On/Off then select ASP.NET 4.6. Then the site started with zero errors. I think Mr Leupold's advice to modify the hosts file with a line for 127.0.0 DNN is a best practice to ensure the localhost is used (vs the internet).