This policy setting lets you determine whether the integrated unblock feature will be available in the logon User Interface ...

This policy setting lets you determine whether the integrated unblock feature will be available in the logon User Interface (UI).

In order to use the integrated unblock feature your smart card must support this feature.  Please check with your hardware manufacturer to see if your smart card supports this feature.

If you enable this policy setting, the integrated unblock feature will be available.

If you disable or do not configure this policy setting then the integrated unblock feature will not be available.