Currently all of our web apps have their Application Pool Identity set to ApplicationPoolIdentity. Now, When an app needs to access some resources on some some server, say, add/read some file, the app performs impersonation in code to a user that has permissions to do this stuff. But now, we are contemplating to create a specific user for each app, and set its app pool identity to its specific new user. But I have noticed in the Advanced Settings dialog that Microsoft recommends to use the application pool identity, as shown in the following image:
Why does Microsoft recommends to use this identity, and is using a specific user is not best practice or a wrong move?
thanks,
ashilon