Enable Http PUT requests on .NET MVC - asp.net-mvc

Question

I'm working on an MVC application. On my original draft of the service I had this method in one of my controllers:
[AcceptVerbs(HttpVerbs.Post)]
[ActionName("UpdateRelationship")]
public ActionResult UpdateRelationship(string aParameter)
And that worked fine. In the latest revision I've been asked to change this into a PUT request to differentiate it from a similar add mechanism which uses post. So I changed it to this:
[AcceptVerbs(HttpVerbs.Put)]
[ActionName("UpdateRelationship")]
public ActionResult UpdateRelationship(string aParameter)
And suddenly I'm getting a 404 on my requests, all from just changing the AcceptVerbs. From the look of the error, it appears as though IIS is trying to route the request as a standard webforms page rather than using MVC extensionless url re-writing.
Googling this it seems that a common cause is browsers not allowing PUT requests but I'm not using a browser to test this - I'm using Fiddler. So there should be no problem there. I also think the correct settings are already in the web.config:
<system.webServer>
<validation validateIntegratedModeConfiguration="false" />
<modules runAllManagedModulesForAllRequests="true">
<remove name="WebDAVModule" />
</modules>
<handlers>
<remove name="UrlRoutingHandler" />
<remove name="MvcHttpHandler" />
<remove name="WebDAV" />
<add name="MvcHttpHandler" preCondition="integratedMode" verb="*" path="*.mvc" type="System.Web.Mvc.MvcHttpHandler, System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
</handlers>
<security>
<requestFiltering>
<verbs>
<add verb="PUT" allowed="true" />
</verbs>
</requestFiltering>
</security>
</system.webServer>
So what have I missed?
EDIT: This code works on a colleagues' machine. So it looks like my local setup of IIS as at fault. Still at a loss to explain what I need to change though - any ideas?
Cheers,
Matt

Answer 1

I had to remove the WebDav Module completely a stated in this blog post
<configuration>
<system.webServer>
<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>
<modules>
<remove name="WebDAVModule" />
</modules>
</system.webServer>
</configuration>

Answer 2

After much fruitless searching and blind alleys involving WebDAV I found the answer on another SO family site :)
https://serverfault.com/questions/93424/how-to-enable-put-and-delete-in-iis7

Answer 3

The configuration that worked for us was the following.
<system.webServer>
<modules runAllManagedModulesForAllRequests="false">
<remove name="UrlRoutingModule" />
<add name="UrlRoutingModule" type="System.Web.Routing.UrlRoutingModule, System.Web.Routing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" preCondition="" />
</modules>
<handlers>
<remove name="ExtensionlessUrlHandler-Integrated-4.0" />
<add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,POST,PUT,DELETE" type="System.Web.Handlers.TransferRequestHandler" resourceType="Unspecified" requireAccess="Script" preCondition="integratedMode,runtimeVersionv4.0" />
</handlers>
</system.webServer>
This is specific to extension-less URLs.
BTW the general recommendation is to set runAllManagedModulesForAllRequests = false.