IIS 7.5 / Windows 7: Error 500.19, error code 0x800700b7

Question

I have been trying to resolve this issue.

I am using Windows 7 and VS2008 +iis7.5. My project is stuck because of this error.

The error says:

Error Summary HTTP Error 500.19 - Internal Server Error The requested page cannot be accessed because the related configuration data for the page is invalid.

`Detailed Error Information
Module  IIS Web Core
Notification    BeginRequest
Handler Not yet determined
Error Code  0x800700b7
Config Error    There is a duplicate 'system.web.extensions/scripting/scriptResourceHandler' section defined
Config File \\?\C:\inetpub\wwwroot\test23\web.config
Requested URL   http://localhost:80/test23
Physical Path   C:\inetpub\wwwroot\test23
Logon Method    Not yet determined
Logon User  Not yet determined
Config Source
   15:         <sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
   16:          <section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptResourceHandlerSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
   17:           <sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebServicesSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
`

I followed the instructions in this Microsoft solution document, but it didn't help. http://support.microsoft.com/kb/942055

Solution

The error is stating that the scriptResourceHandler is being defined twice. The key isn't the 500.19 (something bad happened in the configuration), it's the text of the error.

It's quite common to hit this with the scriptResourceHandler.

In short: remove it from the app's web.config and it should work. Alternatively, add a or entry for it in the web.config, then re-add it.

It's probably defined higher up in the configuration hierarchy somewhere.