WebDAV and WebAPI together cause Error: Handler "ExtensionlessUrlHandler-Integrated-4.0" has a bad module "ManagedPipelineHandler" in its module list

Question

I have both WebDAV installed and running on my site, as a virtual sub site i have a MVC WebAPI site, the API works great, until I try to send a PUT request to it, then i get the below error:

HTTP Error 500.21 - Internal Server Error

Handler "ExtensionlessUrlHandler-Integrated-4.0" has a bad module "ManagedPipelineHandler" in its module list

If I disable WebDAV, then everything works fine and I get no errors. This only happens when WebDAV is enabled.

I have all of the following code in my web.config:

<system.webServer>
  <validation validateIntegratedModeConfiguration="false" />
  <modules runAllManagedModulesForAllRequests="false">
    <remove name="WebDAVModule" />
  </modules>
  <handlers>
    <remove name="WebDAV" />
    <remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" />
    <remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" />
    <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
    <add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
    <add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0" />
    <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
  </handlers>
</system.webServer>

I've tried messing with various app pools.

I've also tired all of the things mentioned in all of these questions:

How to get rid of this error Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its module list

Handler "ExtensionlessUrlHandler-Integrated-4.0" has a bad module "ManagedPipelineHandler" in its module list

How to fix: Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its module list

None of this has solved my issue, is there anything else out there that I have not tried?

Answer 1

@jblaske has a good response.

If you want to remove it temporarily then maybe this article is the best solution.

If you want to remove the handler all together then follow these steps.

1. Open IIS and go to the site in question.
2. Click on "Handler Mappings"
3. Find the handler named "WebDAV"
4. Select it and Remove it

This is my original post.

Answer 2

I started getting this error after I removed WebDAV module and handler manually from IIS to get PUT working. I had to remove "WebDAV Publishing" server role to get over this error. After removing this role and restarting the IIS, PUT is working fine.