The entity type ApplicationUser is not part of the model for the current context

I was having this same problem. I’m doing database first development with an EDMX file. If you are using the connection string generated when adding the EDMX file in :base(“EDMXConnString”) you will most likely have this problem.
I fixed this by creating a standard connection string that pointed to the database where the ASP.NET Identity tables are.

And then used that connection string in :base, and it worked!
public class ApplicationDbContext : IdentityDbContext
{
public ApplicationDbContext()
: base(“MyConnString”)
{
}
}

for me it seems to miss a context instanciation:
UserManagerFactory = () => new UserManager(new UserStore());

should be
UserManagerFactory = () => new UserManager(new UserStore(new ApplicationDbContext()));