Server Configuration Error

Greetings,
I have a web application containing a virtual folder with has a child web application and receiving the following error when accessing the child: "Parser Error Message: Section or group name 'system.web.extensions' is already defined. Updates to this may only occur at the configuration level where it is defined."
Below, is the web.config entry it's complaining about:
<configuration> <configSections> <sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"> <sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3 ...