Whenever a new application pool is created, IIS creates a security identifier (SID) that represents the name of the application pool itself. For example, if you create an application pool with the name "SmartcryptPoolSmartcrypt," a security identifier with the name "SmartcryptPoolSmartcrypt" is created in Windows. Resources can be secured by using this identity. However, the identity is not a real user account and will not show up as a user in the Windows User Management Console.
This can be configured by selecting a folder in Windows Explorer and adding the "SmartcryptPoolSmartcrypt" identity to the folder's Access Control List (ACL).
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