After installing the Service Pack 2 for Vault 2012 Editions and Service Pack 1 for Vault 2013 Editions, the Purge feature is automatically disabled for all migrated vaults. It is disabled so that you can repair existing data (that might have dangling file relationships) before using Purge again.
After repairing your data using the Reference Repair Utility, you can enable Purge through the ADMS Console.
Enable Purge with the ADMS Console
The Purge dialog launches and you can configure your purge criteria.