Known issues on Internet Explorer browsers (MSAL.js)

For better compatibility with Internet Explorer, we generate the Microsoft Authentication Library for JavaScript (MSAL.js) for JavaScript ES5, but there are other things to consider as you develop your application.

Run an app in Internet Explorer

Internet Explorer lacks native support for JavaScript Promises, required by MSAL.js.

To support JavaScript Promises in an Internet Explorer app, reference a Promise polyfill before you reference MSAL.js.


Debugging an application running in Internet Explorer

Running in production

Deploying your application to production (for instance in Azure Web apps) normally works fine, provided the end user has accepted popups. We tested it with Internet Explorer 11.

Running locally

To debug your application locally, temporarily disable Internet Explorer's Protected Mode during your debugging session.

  1. In Internet Explorer, select Tools > Internet Options > Security tab > Internet zone.
  2. Clear the Enable Protected Mode (requires restarting Internet Explorer) checkbox.
  3. Select OK to restart Internet Explorer.

When you're done debugging, follow the previous steps and select (instead of clear) the Enable Protected Mode (requires restarting Internet Explorer) checkbox.

Next steps

Learn more about Known issues when using MSAL.js in Internet Explorer.