This policy setting controls whether the Outlook Protection Rules add-in is enabled.If you enable or do not configure this ...

This policy setting controls whether the Outlook Protection Rules add-in is enabled.If you enable or do not configure this policy setting the add-in automatically downloads Outlook Protection Rules from Exchange and processes them when each Exchange mailbox user composes a new e-mail.  If you disable this policy setting the add-in does not download or process Outlook Protection Rules.