InvalidOperationException: IDX20803: Unable to obtain configuration from

I’m integrating Auth0 into 2 separate ASP.Net MVC applications with OWIN. The first web app uses Auth0 fine. The second, I configured exactly the same way on the same computer. The second is giving the following 2 errors:

InvalidOperationException: IDX20803: Unable to obtain configuration from: 'https://ddks-staging.deltadental.auth0.com/.well-known/openid-configuration’`

[IOException: IDX20804: Unable to retrieve document from: ‘https://ddks-staging.deltadental.auth0.com/.well-known/openid-configuration’.]`

The URL show the configuration JSON properly. When I run the following code, I am not prompted with the Auth0 login screen, but I think it is because the prior 2 errors are preventing it from getting necessary configuration information:

        HttpContext.GetOwinContext().Authentication.Challenge(new AuthenticationProperties
        {
            RedirectUri = Url.Action("Index", "Home")
        },"Auth0");

I’m thinking it is a transport issue and may have something to do with SSL/TLS. I’m running the app in visual studio and have configured debugging to enable SSL. Visual Studio created a self signed cert for the first app and I’m thinking this second app would use the same cert.

Has anyone seen this error or know how to proceed?

Bill

That is indeed intriguing; have you already tried to configure Fiddler globally as a proxy for .NET and see if you can capture different behavior at the network level for the two applications?