AAD Auth Failures - Crossing security zones in Internet Explorer and Microsoft Edge

Applies to: Skype for Business 2015

In this article

Who is this article for?

This article only applies to user error experiences where the browser in use is Internet Explorer (IE) or Microsoft Edge (Edge).

If you are using the Azure AD authentication option to sign into the Skype for Business (SfB) Web SDK in Internet Explorer (IE), you are successfully authenticating to Azure AD and getting redirected back to your web application, and then your sign in fails silently or hangs indefinitely, then this article is for you.

This is especially likely to be an issue if you are hosting your application on http://localhost during development. If this issue is occurring in a production deployment, skip to Crossing Security Zones in Production.

If the previous failure description seems to match your user's experience but the user is not on IE or Edge then you should return to Troubleshooting Azure AD Authentication Failures for Skype Web SDK for a list of other potential issues.

The Issue

Before spending a long time looking at web traffic to detect the issue, try the simple solution proposed by this article. If you want to confirm that this is the specific issue you're hitting, you can use Fiddler or Charles to monitor web traffic between your application and the server. If you have this issue, in your web traffic somewhere after authenticating with AAD, redirecting back to your app page, and initiating signin with signInManager.signIn, you will see a request to login.microsoftonline.com that returned a redirect response. Upon inspecting it, you will see that the fragment of the url itself contains an error, which will say something like this:

ADSTS50058: A silent sign-in request was sent but no user is signed in. The cookies used to represent the user's session were not sent in the request to Azure AD. This can happen if the user is using Internet Explorer or Edge, and the web app sending the silent sign-in request is in different IE security zone than the Azure AD endpoint

The Solution

To fix this issue, you need to ensure that the page where you're hosting your app and the AAD sign in page are treated as though they're in the same security zone.

If this error is occurring during development, the recommended way to fix this is to modify your machine's hosts file to map some dummy domain name (eg. app.myapp.com) to the IP address of localhost ( On a PC, you can follow these instructions to do this:

  1. Open Command Prompt or another terminal in administrator mode.
  2. Enter the following command to go to the directory with the hosts file:

    C:\> cd C:\Windows\System32\drivers\etc

  3. Enter the following to open the hosts file in administrator mode in Notepad

    C:\Windows\System32\drivers\etc> notepad hosts

  4. Add the following line to the bottom of the file to add an entry mapping app.myapp.com to the IP address of localhost: app.myapp.com

  5. Save the file. If it prompts you to 'save as' rather than just 'save,' you probably did not open the file in administrator mode. You must be in administrator mode to modify the hosts file.

    If you've done this correctly, you should now be able to open a browser, navigate to http://app.myapp.com and see the same page you were hosting before on localhost because the domain name app.myapp.com is being resolved to the same IP address as localhost. However now when you try to sign in, your browser should treat app.myapp.com as though it is in the "internet" security zone where the AAD sign in page is located, rather than in the "intranet" security zone where localhost is. You will also have to add the new dummy url to your list of valid reply URLs in the app registration in AAD. For instructions on how to do that, see AAD Auth Failures - Incorrectly configured reply URLs for application. If you have done all this correctly your signin should complete successfully.


Modifying the hosts file is a significant operation and could have an impact on other programs or services. We recommend that you only use this solution during development and undo this change after testing and deploying your app.

Crossing Security Zones in Production

If this error is encountered in a production deployment where the application is no longer being hosted on localhost, then the solution is to manually remove the hosting web application from the Intranet/Trusted security zone.

  1. In IE, open Internet Options
  2. Go to Security > Local intranet > Sites > Advanced
  3. Remove the domain name of the site hosting your web application from the list.

Removing domain name from intranet security zone

You may need to contact your IT administrator as well and ask them to remove any group policy rules that are putting your web application back into the Intranet/Trusted security zones.