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 it throws System.InvalidOperationException: No owin.Environment item was found in the context. This is a known bug, but Microsoft keeps silence about this issue. The easiest way to reproduce this bug - it's to create a new web application (MVC, WebForms or WebApi - doesn't matter) in VS 2013 (with Web Tools 2013 Preview Refresh) and then go to the login page. It will work. Then change namespace in your application to anything else than original namespace and login page will throw that error. Changing namespace back to original (the one you used at the creation of a project) will solve this problem.

It looks like .net stores somewhere something related to the original namespace, but I can't find what and where, it's not in the project folder. I know that stackoverflow is not a place for a bug reports, I just hoping that someone already found a solution for this issue or maybe people involved in the development of ASP.NET Identity will see this.

For me [this](https://stackoverflow.com/a/22650502/8321861) fixed it for me - no credits to me. — Meikel, Mar 13 '18 at 14:33
Note that OwinContext is not accessible from Global.asax See also https://stackoverflow.com/q/24660380/18192 — Brian, Jan 09 '19 at 19:30

score 28 · Accepted Answer · answered Aug 16 '13 at 03:47

28

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.

answered Aug 16 '13 at 03:47

pranav rastogi

4,124
23
23

18

Adding into the web.config fixed this issue. Thank you! – graycrow Aug 19 '13 at 08:44
@pranavrastogi **Voted Down** for missing information! – Mar 31 '20 at 08:23
@graycrow This comment must be **answer**! Thanks a lot. – Mar 31 '20 at 08:23

score 19 · Answer 2 · answered Jul 19 '15 at 18:48

19

I had the same issue, it was fixed after making sure this line was in web.config:

<add key="owin:AutomaticAppStartup" value="true" />

answered Jul 19 '15 at 18:48

cesar-moya

581
5
8

score 19 · Answer 3 · answered Mar 07 '16 at 17:04

19

I had the exact same error, but as it turned out I had another configuration problem in my web.config. My web.config was missing the attribute defaultLanguage="c#" in the compilation element under system.web.

In this case it will default to VB. So unless you have your Startup class written in VB you should change the default language to C#.

Not correct:

<compilation debug="true" optimizeCompilations="true" targetFramework="4.6.1">

This is correct (unless you use VB):

<compilation debug="true" defaultLanguage="c#" optimizeCompilations="true" targetFramework="4.6.1">

answered Mar 07 '16 at 17:04

Drol

189
1
6

6

Thanks. This fixed it for me with an EPiServer Alloy project. – Ken Palmer Jan 31 '18 at 21:57
Tag should be close. Thanks! – Sterling Diaz Jul 12 '18 at 14:04
5

How on earth did you figure that out? – r3mark Apr 16 '19 at 04:41
We tried everything else first and two of us were like 'there is no way this solution is going to fix the issue' and it did. I'm with r3mark "how on earth did you figure this out?" – Michael Adamission Oct 13 '20 at 15:26

score 11 · Answer 4 · answered Oct 30 '15 at 15:17

11

Cleaning ASP.NET temporary files helped me with this exact problem

answered Oct 30 '15 at 15:17

Gatis Bergšpics

441
6
14

Deleting the contents of this specific folder worked for me: c:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files – Vito May 19 '20 at 14:18
I also saw this issue on one of our dev machines and this seemed to fix it at that time. There must be many reasons why this error happens, hence the many solutions. – Michael Adamission Oct 13 '20 at 15:27

score 8 · Answer 5 · answered Aug 20 '13 at 02:10

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.

score 4 · Answer 6 · edited Jan 13 '16 at 10:26

4

If you happened to have copied the below config from MVC4, you should remove it from web.config

<add key="owin:AutomaticAppStartup" value="false" />

edited Jan 13 '16 at 10:26

RobH

3,604
1
23
46

answered Jan 05 '15 at 11:01

Mathi Rajan

79
2

This fixed it for me. – Whelkaholism Dec 19 '16 at 10:00

score 4 · Answer 7 · answered Mar 09 '15 at 20:50

4

I tried everything mentioned on this page but nothing worked. Then I found out about a setting in IIS named owin:AutomaticAppStartup. You can find it in the Application Settings page of the IIS Manager for the Default Web Site. Check to see if that setting is true. If not set to true. This worked for me.

This is the website where I found the answer: http://gotoanswer.stanford.edu/?q=Microsoft.Owin.Host.SystemWeb+and+still+getting+No+owin.Environment+item+was+found+in+the+context

answered Mar 09 '15 at 20:50

Ron Dow

41
1

3

So there are actually two steps: 1 add suggested by Luiz and 2. – Arvind Singh Mar 26 '15 at 11:03
Arvind, could you please post the more of your web.config to show how this works? Thanks! – curious1 Apr 20 '15 at 20:15
1

@Ron, that link is broken – KevinDeus Aug 31 '16 at 21:53
@ArvindSingh - your solution works perfect. We have a sub application hosted as part of the main website and while we had to do the usual "inheritinchildapplications = false" the child application used to fail (not all the time) with this error So for instance it worked 50% of the time and 50% of the time it complained about OWIN. This application was untouched for about 3 years. While it worked fine locally on the server with the other solutions, it won't when you're accessing it off a domain name, hence these 2 statements fit in perfectly in conjunction. – Preetham Apr 19 '20 at 10:57

score 3 · Answer 8 · answered Nov 02 '13 at 21:20

3

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.

answered Nov 02 '13 at 21:20

user2697956

119
1
2

clean the bin and obj directory did the trick for me as well (combined with the web.config alteration). – markwilde Jan 06 '14 at 21:35

score 3 · Answer 9 · answered Jul 10 '18 at 20:13

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.

No need to add Configure(app) inside configuration. It works without that. — anil shrestha, Mar 10 '20 at 17:59

score 1 · Answer 10 · answered May 25 '18 at 11:09

1

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

answered May 25 '18 at 11:09

Zia UsafXai

73
1
10

– Sterling Diaz Jul 12 '18 at 14:14
Note that you should change the Namespace with your own Namespace, and the second [Namespace] with the name of your assembly – Sterling Diaz Jul 12 '18 at 14:14

score 1 · Answer 11 · answered Jul 02 '18 at 09:27

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.

score 0 · Answer 12 · answered Jul 21 '21 at 07:19

I experienced this error in an Optimizely (Episerver) solution where I had two feature branches using the same CMS database. In one feature branch I was working on a proof of concept using a visitor criterion. So I had created something like this:

    public class SomeVisitorCriterionSettings : CriterionModelBase
    {
        public override ICriterionModel Copy()
        {
            return base.ShallowCopy();
        }
    }



[VisitorGroupCriterion(
    Category = "Some category",
    DisplayName = "My visitor criterion")]
public class SomeVisitorCriterion : CriterionBase<SomeVisitorCriterionSettings>
{
    public override bool IsMatch(IPrincipal principal, HttpContextBase httpContext)
    {
        // match logic here..
    }
}

And within Episerver -> CMS -> Visitor Groups I had created an instance of this visitor criterion. After switching to the other branch where this code did not exist, but the instance in the database did, the Owin exception was thrown.

Deleting the visitor criterion in the CMS resolved the issue, but I honestly have no idea why this sort of exception is thrown. I would love to know though..

score 0 · Answer 13 · answered Jul 26 '22 at 09:08

I have tried all of the above suggestions, without success; then reading the documentation at: https://learn.microsoft.com/en-us/aspnet/aspnet/overview/owin-and-katana/owin-startup-class-detection

I understood that the error was in the call to the assembly in the Startup.cs file:

wrong code:

[assembly: OwinStartupAttribute(typeof([AssemblyName].Startup))]

right code:

[assembly: OwinStartup(typeof([AssemblyName].Startup))]

so, I fixed the error removing the word Attribute from OwinStartupAttribute

score -1 · Answer 14 · answered Mar 02 '17 at 12:09

-1

adding default language to compilation in web.config did it for me!

answered Mar 02 '17 at 12:09

David

1

Welcome to the Stack Overflow. You should add some description to your answer. One sentence isn't usually enough. – filipst Mar 02 '17 at 12:51
its important that defaultLanguage is set to C# – David Mar 09 '17 at 12:33
so is it exactly the same as this answer created year before yours? https://stackoverflow.com/a/35849641/2170171 – Lanorkin Aug 16 '17 at 08:20

No owin.Environment item was found in the context

14 Answers14

Linked