Internet Explorer is displaying multiple pop-up windows for authentication when opening the browser. This is experienced when using an authentication realm with basic credentials (for instance, LDAP or IWA Basic).

Entering correct credentials for all the prompts will load the page.

Internet Explorer is using child processes to perform authentication and additional requests. This creates a concurrency issue. The result is the queuing of authentication requests for each resource on the page.

After implementing the below solution of enabling protected mode, the requests are made from the main process so additional resources will be authenticated correctly.

The following Fiddler output shows this behavior when Protected Mode is disabled:

The following Fiddler output shows the behavior once switching to protected mode:

1. Open Internet Explorer
2. Navigate to Tools > Internet Options
   
3. Navigate to the Security tab, select "Internet" and check "Enable Protected Mode".
   
4. Select "Local Intranet" and check "Enable Protected Mode".
   
5. Select "Trusted Sites", check "Enable Protected Mode", then click "OK".
   
6. Re-launch Internet Explorer and verify only one prompt is displayed