Enterprise Vault™ Managing Retention
About storage expiry
When you configure storage expiry in site properties, the Enterprise Vault Storage service automatically deletes items from archives when the items' retention periods have expired, or a fixed expiry date is reached.
By default, the start of a retention period is based on the item's modified date. For mail messages, the modified date is the date and time when the message was received. For documents, the modified date is the date and time when the document was last modified. You can configure Enterprise Vault to base expiry on the item's archived date instead.
If you base expiry on the item's archived date, and use Exchange Server Archiving, you may need to consider calendar, meeting, or task items that have an end date in the future. If storage expiry for your site is based on the archived date of an item, then items with an end date in the future could be deleted by storage expiry before the end date of the item. To prevent this, you can create a retention category that Enterprise Vault will apply automatically to these items when they are archived. You specify this retention category in the advanced settings of the Exchange mailbox policy.
If you import old items into Enterprise Vault from other mail systems, expiry based on the archived date can be useful. If the items are very old and storage expiry in Enterprise Vault is based on modified date, the items could expire immediately on import into Enterprise Vault.
Although you configure the default settings for storage expiry in site properties, you can configure in retention category properties whether to use a fixed expiry date, or a retention period that is based on the modified or archived date. If the settings in a retention category differ from the settings in the site properties, then the setting value for the retention category takes precedence for items that are assigned the retention category.
Options in retention plan properties and classification policies allow you to assign different retention categories to items, and specify when a retention category is assigned to an item. For example, if you assign a different retention category to items when their retention period expires, you can control whether Enterprise Vault deletes the item. If you are planning to implement the Enterprise Vault Classification feature or retention plans, or both, we recommend that you give careful consideration to the impact on storage expiry.