This policy setting hides the "Send Latest Version" button and prevents it from appearing on out-of-date meeting forward ...

This policy setting hides the "Send Latest Version" button and prevents it from appearing on out-of-date meeting forward notifications and responses.

If you enable this policy setting, the "Send Latest Version" button be hidden on out-of-date meeting forward notifications and responses.  

If you disable or do not configure this policy setting, the "Send Latest Version" button will be turned on.