ASP.NET Web API - elmah.axd 404 error - No HTTP resource was found that matches the request URI 'http://.../elmah.axd'

If you've installed ELMAH on your ASP.NET Web API project and get the error "No HTTP resource was found that matches the request URI 'http://.../elmah.axd'" then you may have done the same thing as me.

When I first got this error I thought maybe ELMAH just didn't play nicely with Web API yet, but just to double check I installed it on a fresh new Web API project and it worked fine! I then went through a long and agonising process of elimination to figure out what in my application was preventing ELMAH from displaying before finally I found the culprit.

The problem was that I had removed the 'api' prefix from the default route in WebApiConfig.cs, so instead of "api/{controller}/{id}" I have just "{controller}/{id}". This is because my api is running on it's own subdomain "" rather than having it sitting off the primary domain as "".

To fix the issue I added the following ignore rule to Global.asax.cs:

public class WebApiApplication : System.Web.HttpApplication
    protected void Application_Start()


The thing that had me stumped for a while was that ignoring the route in the WebApiConfig.cs didn't work, you have to ignore it on the RouteTable.Routes (RouteCollection) collection, not on the config.Routes (HttpRouteCollection) collection.


Subscribe or Follow Me For Updates

Subscribe to my YouTube channel or follow me on Twitter, Facebook or GitHub to be notified when I post new content.

Other than coding...

I'm currently attempting to travel around Australia by motorcycle with my wife Tina on a pair of Royal Enfield Himalayans. You can follow our adventures on YouTube, Instagram and Facebook.

Need Some ASP.NET Help?

Search fiverr to find help quickly from experienced ASP.NET developers.

Supported by