MIM 2016 - Password Registration portal - Not Authorized HTTP Error 401. The requested resource requires user authentication.

Hi,

I have installed Password Registration and Reset Portals but when I try to access it threw an Error as below,

Found similar issue posted on https://social.technet.microsoft.com/Forums/en-US/484faae8-4df6-4b81-8b2d-9d75d5258e4f/fim-portal-http-error-401-the-requested-resource-requires-user-authentication?forum=ilm2

Had not configured,

• Kerberos Delegation - As per my understanding Kerberos Delegation might not be required for Password registration/reset portals.
  
• useAppPoolCredentials="true" - When I configure this I get Error 500.0 when I try to access Password Registration page. Error as shown below

Appreciate if someone can help with this. Thanks.

Regards, Chandan