Are you using your own global.asax? It should inherit from Umbraco.Web.UmbracoApplication. 

Other than that, in a clean install this works.

Make sure to check out my (very much work in progress) v6 examples site: https://github.com/nul800sebastiaan/Umbraco6Examples

It shows you better ways of mixing umbraco and controllers/views. 

Basically: If you need a form to be handled by a controller:

• Create page with a template (MyTemplate.cshtml, an MVC View in ~/Views inheriting from UmbracoTemplatePage)
• Create a partial view for the form, use Html.BeginUmbracoForm to wrap the form, the model is your model class (@model MyModel)
• On your MyTemplate, add the partial and pass it an instance of your model: @Html.Partial("~/Views/Partials/MyForm.cshtml"), new MyModel())

Thanks sebas. I have the standard global.asax. But after fiddling around a bit more I found out that the URL syntax is a little different than documented and it is not picking up default actions. So I'm able to request the web api using this syntax:

http://umbraco.local/Umbraco/Api/MyApi/Post

Notice the extra Api appended to the controller name and also the mandatory action name at the end (Post). Should I file this as a bug or am I misundertanding something about the URL syntax?

I haven't had success with directly requesting the SurfaceController using the same technique though:

http://umbraco.local/Umbraco/Surface/MySurface/Index
Doesnt' work. But then maybe it  is not supposed to be requested directly as per your example project. 

I've also had a look at your Umbraco6Example project. I now understand more about how the Surface controllers work and how they are hooked up using Html.BeginUmbracoForm. Would be great though if you could add a demonstration of how to use the new Localization API's so that I can solve this problem too.

Have you manage to solve this problem? I'm having the same but my surfacecotroller works fine in my dev environment but on production it gives a 404

You need to have the namespace in your controller.

This will not work

public class SearchController : SurfaceController
{
    ...
}

but this will

namespace Controllers
{
     public class SearchController : SurfaceController
     {
         ...
     }
}

If you have umbraco v6 the routing will work without the namespace, but umbraco v7 for some reason requires it.

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