One of our developers got this error while locally configuring ASP.NET 4.0 website on his local IIS 7 server:
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"
To fix this issue, follow these steps:
1. Go to C:\Windows\System32\inetsrv\config and edit the applicationHost.config file.
2. Modify these values below located in section <configSections> <sectionGroup name="system.webServer"> in the applicationHost.config file: