No owin.Environment item was found in the context

Question

Microsoft recently introduced new ASP.NET Identity - replacement for old (Simple)Membership. Unfortunately, I can\'t use this new membership system in my old project because

Answer 1

I created two new projects called TesteMvc5.2 and TesteMvc5.0 and both of them didn't work at start

this is because the default namespace is different from the assembly name. but after I put the line

<add key="owin:AppStartup" value="TesteMvc5._2.Startup, TesteMvc5.2" />

on the web.config it worked fine.

Answer 2

None of the above answers worked for me.

Turned out my project was missing the "Startup" class that contains the following:

using Microsoft.Owin;
using Owin;

[assembly: OwinStartupAttribute(typeof(NAMESPACE.Startup))]
namespace NAMESPACE
{
    public partial class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            ConfigureAuth(app);
        }
    }
}

This file called "Startup.cs" is located on the root folder (~/) of your project.

My "Web.config" doesn't have any of this "Owin" configuration posted on the other replies.

Answer 3

Had same problem. Thanks for the shared solutions. this..

<add key="owin.AppStartup" value="Namespace.Startup, Namespace"/>
<add key="owin:AutomaticAppStartup" value="false"/>  

fixed for me

Answer 4

I have no idea why this works but it did!

My problem was in VS2013. In the WebConfig, debug was set to true and I got that error. When I set it to false it worked fine and then I reset to true and it continued to work OK!

At first when debug was true before changing to false, I put a break point in my StartUp code and it wasn't reached at all. After changing to false pressing save and then back to true the StartUp code was called and the program works like it should.

Answer 5

I had this same issue. I fixed it with the web.config.

However I had changed the assembly name and namespace and did not find the original assembly name anywhere anymore.

I then discovered that clean was not removing the original assembly from the bin.

Aftter deleting the bin litter, I was able to remove the web.config OWIN entry.

Answer 6

Most likely it cannot find the OWIN Startup class. The default convention for the Startup class is [AssemblyName].Startup. If you're no longer following that convention you'll need to specify the full name of your Startup class in the Web.Config.

The next release of Microsoft.Owin.Host.SystemWeb package now throws detailed exception messages when the Startup class cannot be found.