I am attempting to run an application in IIS8 that has the following in the config:
<modules runAllManagedModulesForAllRequests="true" />
IIS8 is giving me an error that says...
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".
I'm guessing by the error and a quick SO search that there is some higher level security setting that's preventing that line from being allowed. Any ideas?
I've solved the same problem by installing the window features "Internet Information Service/World Wide Web Service/Application Development/ASP.NET x.x" in the Control Panel of Windows8. If you want to setting on Windows Server 2012, the following link gives you hint. http://www.iis.net/learn/get-started/whats-new-in-iis-8/iis-80-using-aspnet-35-and-aspnet-45
hope that it works out.
For those of you running Windows Server 2012 the Application Development features are found at
[] Server Roles
[] Web Server IIS
[] Web Server
[] Application Development
[] ASP.NET x.x
When you select the .NET version it will ask if you want to add Extensions and other features. I just said yes, but you may be able to get away without installing those.
its hard to give a specific answer here, but the basics of it are that you need to look at the machine.config for the box you're running on. find the system.webServer node and look for the 3 tags/attributes its referencing in the error. chances are you'll find something that is marked as not overridable (allowOverride="false"), but i've not messed with windows 8/server 2012 yet, so i don't know what the machine.config looks like.
来源：https://stackoverflow.com/questions/12486089/iis8-win8-and-runallmanagedmodulesforallrequests-true