WebAPI Delete not working - 405 Method Not Allowed

Question 1

I found the solution eventually! If you come across the same issue, add the following to your web.config

<system.webServer>
    <validation validateIntegratedModeConfiguration="false"/>
    <modules runAllManagedModulesForAllRequests="true">
        <remove name="WebDAVModule"/> <!-- ADD THIS -->
    </modules>
    ... rest of settings here

I hope this helps

Question 2

In some cases removing it just from modules can produce next error:

500.21 Handler "WebDAV" has a bad module "WebDAVModule" in its module list

Module: IIS Web Core Notification: ExecuteRequestHandler"

solution was suggested here. Also need to remove it from handlers.

<system.webServer>
    <modules>
        <remove name="WebDAVModule" />
    </modules>
    <handlers>
        <remove name="WebDAV" />
    </handlers>
</system.webServer>

Question 3

In my case none of the above solutions was working. This was because I had changed the name of the parameter in my Delete method.

I had

public void Delete(string Questionid)

instead of

public void Delete(string id)

I need to use the id name because that's the name that is declared in my WebApiConfig file. Note the id name in the third and fourth lines:

            config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

I got this solution from here.

Question 4

The Javascript for HTTP DELETE verb must be like this:

$.ajax({
    **url: "/api/SomeController/" + id,**
    type: "DELETE",
    dataType: "json",
    success: function(data, statusText) {
        alert(data);
    },
    error: function(request, textStatus, error) {
        alert(error);
        debugger;
    }
});

Do not use something like this:

...
data: {id:id}
...

as when you use the POST method.

Question 5

If you are using IIS 7.0 or later version. This issue is mainly related to WebDAV extension module on IIS server. this happened while Using Post OR delete action.

Please try below setting in web config

<system.webServer>
   <modules>
       <remove name="WebDAVModule" />
   </modules>
   <handlers>
     <remove name="WebDAV" />
   </handlers>
</system.webServer>

Question 6

After trying almost every solutions here this worked for me. Add this in your APIs config file

<system.webServer>
    <handlers>
      <remove name="WebDAV" />
      <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>
    <modules>
        <remove name="WebDAVModule" />
    </modules>
</system.webServer>

Question 7

I also had the same problem, I am calling WebAPi and is getting this error. Adding following configuration in web.config for services solved my problem

    <modules runAllManagedModulesForAllRequests="true">
        <remove name="WebDAVModule"/> <!-- add this -->
    </modules>

in web.config file solved my problem. This is How i was calling from client side

using (var client = new HttpClient())
{
    client.BaseAddress = new Uri(environment.ServiceUrl);
    client.DefaultRequestHeaders.Accept.Clear();
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    HttpResponseMessage response = client.DeleteAsync("api/Producer/" + _nopProducerId).Result;
    if (response.IsSuccessStatusCode)
    {
        string strResult = response.Content.ReadAsAsync<string>().Result;
    }
}

Question 8

Go to applicationHost.config (usually under C:\Windows\System32\inetsrv\config) file and comment out the following line in applicationHost.config

1)Under <handlers>:

<add name="WebDAV" path="*" verb="PROPFIND,PROPPATCH,MKCOL,PUT,COPY,DELETE,MOVE,LOCK,UNLOCK" modules="WebDAVModule" resourceType="Unspecified" requireAccess="None" />

2)Also comment out the following module being referred by the above handler under <modules>

<add name="WebDAVModule" />

Question 9

In my case, I missed to add {id} to the [Route("")] and I got the same error. Adding that fixed the problem for me: [Route("{id}")]

Question 10

I had 405 error Method Not Allowed because I had omitted to make the Delete method on the WebApi controller public.

It took me a long time to find this (too long!) because I would have expected a Not Found error in this case, so I was incorrectly assuming that my Delete method was being denied.

The reason for Not Allowed rather than Not Found is that I also had a Get method for the same route (which will be the normal case when implementing REST). The public Get function is matched by the routing and then denied because of the wrong http method.

A simple error I know but it may save someone else some time.

Question 11

Just to add. If this is your config

config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }

please keep doing as Hugo said, and do not set Route attribute to the controller get method, this gave a problem in my case.

Question 12

I had the similar issue but for PUT - none of the other suggestions worked for me.

However i was using int rather than the default string for the id. adding {id:int} to the route solved my problem.

    [Route("api/Project/{id:int}")]
    public async Task<IHttpActionResult> Put(int id, [FromBody]EditProjectCommand value)
    {
       ...
    }

Question 13

We had to add custom headers to our web.config as our request had multiple headers that confused the API response.

<httpProtocol>
    <customHeaders>
        <remove name="Access-Control-Allow-Methods" />
        <remove name="Access-Control-Allow-Origin" />
        <remove name="Access-Control-Allow-Headers" />
    </customHeaders>
</httpProtocol>

Question 14

[HttpPost] attribute on the top of Delete method solved this issue for me:

[HttpPost]
public void Delete(int Id)
{
  //Delete logic
}