HTTP Error 500.19 - Internal Server Error There is a duplicate 'system.web.extensions/scripting/scriptResourceHandler' section defined
After the recent Windows updates installation on our 2008 R2 server, all of a sudden all the web applications hosted in IIS 7.0 started throwing the HTTP error 500.19 with the following details: 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\XXXX\web.config Requested URL http://localhost:80/XXXX Physical Path C:\inetpub\wwwroot\XXXX Logon Method Not yet determined Logon User Not yet determined Config Source 14: <sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=3.5.0.0, C