KB33063: The Windows authentication login box keeps appearing when trying to access MicroStrategy Web 9.4.1 and 10.x

SYMPTOM:
When trying to access Strategy Web 9.4.1 and 10.x,  users are prompted for credentials to connect to a web server configured to use anonymous access.  The prompt window in a Internet Explorer browser is shown below:
 

 
CAUSE:
One possible cause for this prompt to appear is that the login account on the machine hosting the Strategy Web server is not configured correctly.
 
ACTION:
In order to configure the server correctly, users need to create an anonymous account on IIS as indicated on the steps below:

1. In the Windows machine hosting the web server, go to Start > Run and type "Control userpasswords2"  as shown below:

• Click on 'Add' to create a new user and type in 'IUSR_' to create the required account. Make sure to set a password for the user account using the 'Change Password' button.
• Go to In the 'IIS Manager' and click on 'Default Web Site', then go to Authentication and make sure Anonymous is enabled:

• Click 'OK' to save the changes and restart IIS.
• Note: Refer to article KB11183: Is it possible to setup Standard Authentication and NT authentication at the same time in MicroStrategy Web?  for more information on whether Anonymous access and Integrated Windows Authentication can be set up at the same time. 

 
WARNING:
The third-party product(s) discussed in this technical note is manufactured by vendors independent of Strategy. Strategy makes no warranty, express, implied or otherwise, regarding this product, including its performance or reliability.