Getting 404 error with custom Web API [duplicate]

Question

We have Sitecore 9.0 update 2 site running on Windows Server 2016. We've added a custom web api controller. We are able to successfully request the custom web api methods on our local environment and the CD environments, but are getting 404 errors on the DEV standalone environment and all CM environments.

Has anyone else experienced/resolved this issue?

Answer 1

Add below patch file to allow controller:

<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <api>
      <services>
        <configuration>
          <allowedControllers>
            <allowedController desc="XXX">XXX,XXX</allowedController>
          </allowedControllers>
        </configuration>
      </services>
    </api>
  </sitecore>
</configuration>

Answer 2

Thanks everyone for your replies. I was able to resolve this problem thanks to the answer given here:

WebAPI Controllers not being found in Sitecore 8.2

Per Ben Lipson:

Web API is apparently really aggressive when it caches API Controller types. I was able to fix my issue by doing the following:

1. stop IIS
2. kill the w3wps
3. navigate to C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root and obliterate anything in this folder

Answer 3

Just to know:

404 error means that application cann`t find corresponding route to process your request by some reasons.

It is easy to check all registered routes in any place in code by:

var registeredRoutesData = RouteTable.Routes.GetRouteData(new HttpContextWrapper(HttpContext.Current));

(The most common reasons: some config files with route initializers are missing on specific environment or otherwise - environment has its own extra configs that overwrite needed routes).