The argument type is not assigned to the parameter type although it inherits

I tried to write an id MVC application from scratch. For this I followed two tutorials from Ben Foster ( Tutorial Part1 and Tutorial Part2 )

But I am stuck with the second tutorial - Configuring UserManager. The following line doesn't work for me:

    // configure the user manager
    UserManagerFactory = () =>
        var usermanager = new UserManager<AppUser>(
            new UserStore<AppUser>(new AppDbContext()));


Visual Studio highlights

new AppDbContext()


and will show me the following message:

The argument type "MyProject.DbContext.AppDbContext" is not assigned to the parameter type "System.Data.Entity.DbContext"

I don't understand why this doesn't work in my solution because I followed the tutorial completely. My AppDbContext looks like this:

namespace MyProject.DbContext
    using MyProject.Models;

    using Microsoft.AspNet.Identity.EntityFramework;

    public class AppDbContext : IdentityDbContext<User>
        public AppDbContext()
            : base("DefaultConnection")


My user class:

namespace MyProject.Models
    using Microsoft.AspNet.Identity.EntityFramework;

    public class User : IdentityUser
        public string Name{ get; set; }


I also downloaded the source code from Ben and tried to run it and it works without issue. I guess it doesn't matter that all my files are not in the same folder ?!

Hope you can help me. It's really frustrating if a simple tutorial doesn't work as it should ...

Regards, winklerrr


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2 answers

I solved the problem by removing all links that had something to do with owin and Idendity and read them again.

I think the problem was caused by a mismatch between the referenced dlls and the actual dlls used ... (Played with the Package Manager Console.)



Yours UserManager

accepts AppUser

as a generic type: UserManager<AppUser>

when db-context accepts User

as a generic parameter. AppUser

and User

are not the same classes.

Your user-defining class should be the same everywhere.



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