Multiple types were found that match the controller named 'Home'

Question

I currently have two unrelated MVC3 projects hosted online.

One works fine, the other doesn't work, giving me the error:

Multiple types were found that match the controller named 'Home'. This can happen if the route that services this request ('{controller}/{action}/{id}') does not specify namespaces to search for a controller that matches the request.

If this is the case, register this route by calling an overload of the 'MapRoute' method that takes a 'namespaces' parameter.

The way my hoster works is that he gives me FTP access and in that folder I have two other folder, one for each of my applications.

ftpFolderA2/foo.com

ftpFolderA2/bar.com

foo.com works fine, I publish my application to my local file system then FTP the contents and it works.

When I upload and try to run bar.com, the issue above fires and prevents me from using my site. All while foo.com still works.

Is bar.com searching from controllers EVERYWHERE inside of ftpFolderA2 and that's why it's finding another HomeController? How can I tell it to only look in the Controller folder as it should?

Facts:

1. Not using areas. These are two COMPLETELY unrelated projects. I place each published project into each respective folder. Nothing fancy.
2. Each project only has 1 HomeController.

Can someone confirm this is the problem?

Solution 1

This error message often happens when you use areas and you have the same controller name inside the area and the root. For example you have the two:

• ~/Controllers/HomeController.cs
• ~/Areas/Admin/Controllers/HomeController.cs

In order to resolve this issue (as the error message suggests you), you could use namespaces when declaring your routes. So in the main route definition in Global.asax:

routes.MapRoute(
    "Default",
    "{controller}/{action}/{id}",
    new { controller = "Home", action = "Index", id = UrlParameter.Optional },
    new[] { "AppName.Controllers" }
);

and in your ~/Areas/Admin/AdminAreaRegistration.cs:

context.MapRoute(
    "Admin_default",
    "Admin/{controller}/{action}/{id}",
    new { action = "Index", id = UrlParameter.Optional },
    new[] { "AppName.Areas.Admin.Controllers" }
);

If you are not using areas it seems that your both applications are hosted inside the same ASP.NET application and conflicts occur because you have the same controllers defined in different namespaces. You will have to configure IIS to host those two as separate ASP.NET applications if you want to avoid such kind of conflicts. Ask your hosting provider for this if you don't have access to the server.

Solution 2

Here is another scenario where you might confront this error. If you rename your project so that the file name of the assembly changes, it's possible for you to have two versions of your ASP.NET assembly, which will reproduce this error.

The solution is to go to your bin folder and delete the old dlls. (I tried "Rebuild Project", but that didn't delete 'em, so do make sure to check bin to ensure they're gone)

Solution 3

In MVC4 & MVC5 It is little bit different, use following

/App_Start/RouteConfig.cs

namespace MyNamespace
{
    public class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
                namespaces:  new[] {"MyNamespace.Controllers"}
            );
        }
    }
}

and in Areas

context.MapRoute(
                "Admin_default",
                "Admin/{controller}/{action}/{id}",
                new { action = "Index", id = UrlParameter.Optional },
                new[] { "MyNamespace.Areas.Admin.Controllers" }
            );

Solution 4

Watch this... http://www.asp.net/mvc/videos/mvc-2/how-do-i/aspnet-mvc-2-areas

Then this picture (hope u like my drawings)

Solution 5

in your project bin/ folder

make sure that you have only your PROJECT_PACKAGENAME.DLL

and remove ANOTHER_PROJECT_PACKAGENAME.DLL

that might appear here by mistake or you just rename your project

View more solutions

Comments

[Only Bolivian Here]

I'm not using areas at all. These are two completely unrelated applications residing in separate folder inside an FTP root folder. Maybe my application is looking for MVC controllers everywhere it can and that reach just so happens to extend to the other Home Controller. How can I tell it to not look anywhere but it's own Controller folder and disregard the rest?

[Darin Dimitrov]

@SergioTapia, it seems that they are pretty related your applications. Your hosting provider put them inside the same ASP.NET application. You will have to ask him split them in IIS as separate instances or you will have lots of problems.

[Don McCauley]

Thanks this is simple and does the job.

[om471987]

Thanks. In ASP MVC 4.0 you need to pass named argument like namespaces: new[] {"AppName.Areas.Admin.Controllers" }

[Travis J]

+1 - Works well. I didn't realize there was a separate area for route registration in areas. Everywhere I look it seems there is a quality answer from Darin :)

[Aruna]

Solved the issue..! :)

[Paul Zahra]

This bit me when copying a project and renaming it... the old project named dll was still in the bin, a cleanup didn't remove it... I had to manually delete it!

[Abhimanyu]

your suggestion saved me

[katesky8]

me too, thanks , clean dosnt actually mean clean , grrrr

[keithl8041]

Is there a way of doing something similar in Web Api 2? The fourth argument for the Routes.MapHttpRoute only takes constraints and doesn't understand the namespace argument.

[Form]

This was the fix for me. My publish profile did not remove files not present locally, so my app picked up old dlls in addition to new ones and found duplicate types.

[Sebastian 506563]

Other variation of this error is when you use resharper and you use some "auto" refactor options that include namespace name changing. This was what happen to me.

[Adriaan Davel]

This happened to me when I copied to contents of 1 project over the contents of another. I had to delete the specific files from the bin folder

[Mauro Valvano]

I changed my project name and i refractored all the files but then i got this error. Deleting the bin folder worked for me too.

[Tom Blodget]

If you are getting this from an Azure App Service, go to https://<your_app_name_here>.scm.azurewebsites.net/DebugCons‌​ole to log in and delete files.

[DanKodi]

Yes It's not enough to just provide a namespace in MapRoute. The namespace provided here need to match the namespace of the controller class resides in. Now it works!

[brando]

Thx this was the problem for me. I'd created a "new" project by copy/pasting an existing project into a new folder; the old build dlls came with, deleting bin folder wiped it clean

[Karthic G]

hi, I've tried yours code, but it comes an error again The request for 'Health' has found the following matching controllers: Lovefreerangeeggs.Areas.Admin.Controllers.HealthController Lovefreerangeeggs.Controllers.HealthController, What should I do?

[Roberto Bonini]

I got this when moving my project files to a second drive. Clearing out the bin folder solves it. Oddest darn thing.

[Troy Grosfield]

Well that was a painfully annoying error with a very simple fix. Thanks!

[Ravi Anand]

great solution if you have same controllers in multiple projects

[Jason Beck]

This was the case for me. If you truly have multiple controllers with the same name, this may be needed after you've added namespaces to your route definitions. For example, for your homepage where the controller and area aren't explicitly chosen by the path.

[Patrick Borkowicz]

This occured for me when I had an OData controller and an MVC controller with the same name (different namespaces), except in my case the error message also said different namespaces are not supported for OData routes, and indeed, the OData route config does not accept a namespaces parameter like WebAPI config does. The error also ONLY OCCURED ON MY AZURE PRODUCTION SERVER, after combining code from a couple of projects. To fix the issue, I used FTP to connect to the Azure site, cleared the root dir, and redeployed.

[AnotherDeveloper]

@TomBlodget Thank you. This was what I needed. I was able to set a delete previous files option on the publishing profile, but basically, it's the same as your solution.

[Gavin Ward]

If you are using areas and want to namespace the controllers, you need to namespace both the routes inside the area and outside. Only namespacing the area route still gave me this issue.

[Mike]

Thank you @DrTJ This was soooooo frustrating! You expect the dang clean process to work and expectations is the root of failure. This saved me pulling out my hair further!

[Satish Kumar sonker]

i was facing the similar issue. and main reason was that i had the same controller in two different Area

[Mavi Domates]

same here this was the case for me. Thanks a lot!

[Derreck Dean]

In the project I work on, we have a main turnkey backoffice with areas for custom client work. Each one has a 'settings' controller. This answer is a great alternative to having to define a route for the settings controller for each area.

[Yeronimo]

This was the problem for me. A colleague added by mistake a reference from one front-end project to another creating this issue. He removed the reference, thus Visual Studio also removing the dll files on his disk. I pulled the update from Git, references were gone, but the dll files remained, evenafter a clean. Simply because my VS didn't see the reference anymore. But when running IIS saw the files and used them. Removing them from my disk helped.

[Saravanan Sachi]

Seems Clean and Rebuild don't clear bin folder. Manually we have to delete.

[Detilium]

Exactly my issue. Thank you.

[Carlos Muñoz]

@ppumkin tell that to a blind programmer. The text can be read by screen readers though

[Piotr Kula]

Hi Carlos. Yes I understand the situation. It is already tough explaining it people without visibility disabilities. I am not even sure any kind of assistive software would be able to describe what is going on in the picture well to any body. It does bring to attention that the answer should probably have text at least trying to describe what is going on.

[Erik Frantz]

This is what I was running into, confirming my suspicions.

[eyal]

Worked for me! thnks!

[apc]

I had changed the assembly name and had some old dlls sitting in the bin. Thanks

[Vash]

Thank you! I cannot believe I missed something so simple.

[Milad]

For me after clean up I had to modify Global.asax code behind

[ransems]

"AppName.Controllers" is actually "MyNamespace.Controllers" for clarity, in case you are looking for the AppName registered somewhere, it's just the namespace of the controller that should be the default route handler.

[AlejandroDG]

Thanks MATE, this was my problem, damn VS clean useless method.

[suttonb1]

9 years later, and I just ran into this issue. Made a copy of a project with a new name. Published the new project. Was working fine in my new dev environment, but not when I overwrote the existing staging and prod sites. This was exactly the reason! Thanks so much!