Resolving Config Error to run Central Administration

By: MJ Ferdous | Comments | Related: > SharePoint Configuration

Problem

Let's say you have already installed SharePoint 2010 on your server and you recently upgraded IIS7 / 7.5 to ASP.NET 4.0. Or you might changed the "SharePoint Central Administration V4" application pool’s .NET framework from version 2 to 4. You may got an error...

There is a duplicate 'system.web.extensions/scripting/scriptResourceHandler' section defined

...when you try to run central administration or any SharePoint application.

Solution

This problem occurs because when you use the .Net framework 4.0 and the machine config already has all those sections defined. The error message (scriptResourceHandler) can be initially resolved by commenting out the handler in the web.config. But then there could be other errors (other duplicates). Finally it causes an authentication problem after commenting out all the duplicates.

Step 1:

When you run SharePoint Configuration Wizard to fix this, you may get the following error:

This issue occurred due to running the SharePoint Application pool under the .NET framework 4.0. However, the application is compiled with .NET framework 3.5. SharePoint 2010 is running under .NET framework 3.5. So, in this case, please make sure the application pool is running under .NET framework 3.5.

Step 2:

Do the following to reset the Application Pool

Open the Internet Information Server(IIS) manager.
Go to "Application Pools".
Double-click the application pool that the web application is using . (This web application is on port 46824.)
Change its .NET framework version to V2.0.50727 .
Re-Start IIS.