asp.net - IIS Config Error - This configuration section cannot be used at this path

Question

I am getting the below error when I try to run my website.

The website is hosted on Windows 2012 R2.

Config error: 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".

Error Code : 0x80070021

Config Source:

 60:     <httpErrors errorMode="Detailed" />
 61:     <handlers>
 62:       <remove name="ExtensionlessUrlHandler-Integrated-4.0" />

Below is what all I have tried:

1. Installed .Net 3.5 using "Add features and roles" in IIS

2. In the applicationHost file I have made the below code changes:

   Changed sections handlers', modules, anonymousAuthentication, basicAuthentication,etc overrideModeDefault from "Deny" to "Allow".

3. Have done "HTTP Activation" in .Net 3.5 as well as 4.5.

Below is my web config file handler code:

<handlers>
  <remove name="ExtensionlessUrlHandler-Integrated-4.0"/>
  <remove name="OPTIONSVerbHandler"/>
  <remove name="TRACEVerbHandler"/>
  <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0"/>
</handlers>

4. Installed all the features in features windows in this path: Internet Information Service --> World Wide Web Services --> Application development features --> All but CGI have been enabled.

5. In feature delegation ASP was Read Only earlier, I have changed it to Read/Write

6. Unlocked handlers using command prompt

But I am still unable to get rid of the error. My local instance is working perfectly fine. Also, I have a development server on which this website is working, only in my production server I am getting this error.

Please help me to find out what might be causing this problem.

Answer 1

Follow the below steps to unlock the handlers at the parent level:

1) In the connections tree(in IIS), go to your server node and then to your website.

2) For the website, in the right window you will see configuration editor under Management.

3) Double click on the configuration editor.

4) In the window that opens, on top you will find a drop down for sections. Choose "system.webServer/handlers" from the drop down.

5) On the right side, there is another drop down. Choose "ApplicationHost.Config "

6) On the right most pane, you will find "Unlock Section" under "Section" heading. Click on that.

7) Once the handlers at the applicationHost is unlocked, your website should run fine.