Managed Folders: Why aren't Calendar items expired?

You're testing Exchange 2007's Messaging Records Management (MRM) features to implement your organization's messaging retention policies.

You create a new Managed Folder for Calendar items, and then create a Managed Content Setting for it to expire Calendar items in 1 year. Next, you create a Managed Folder Mailbox Policy and add the Managed Folder to the Policy. You apply the policy to a test mailbox.

Testing the Managed Folder Policy
You open the test mailbox, create a single-instance appointment that starts and ends on some date more than a year ago.

To test the new Managed Folder Policy, you manually run the Managed Folder Assistant against your test mailbox:

Start-ManagedFolderAssistant -Mailbox "Joe Adams"

You expect the meeting, which (starts and) ends at some date more than a year ago, to be expired and the RetentionAction specified in the Managed Content Setting to be applied. It doesn't.

Calculating Retention Age for Calendar items

You can tell the MFA when to start counting an item's retention age from, by specifying it in the Content Settings for a Managed Folder. It can be based on:
1) When the item was delivered to a mailbox or
2) When the item was moved to a folder


Figure 1: Configuring retention period in Managed Content Settings

Calendar items such as meetings and appointments, and Tasks, are treated differently since these items have an end date. You could create a meeting for a future event, or create a recurring meeting that takes place at a certain interval (daily/weekly/monthly/yearly) during a certain period, or indefinitely. Therefore, the end date of these items needs to be considered when expiring them. Recurring meetings will expire based on the end date of the last occurrence. Meetings with no end date do not expire.


Figure 2: Recurring meetings can be scheduled to occur daily, weekly, monthly, or yearly for a long period, or indefinitely. When expiring such items, the MFA considers the end date.

If these items are deleted, and thus end up in the Deleted Items folder, the end date is no longer a factor. The Managed Folder Assistant expires Calendar items in the Deleted Items folder based on the message-received date. If the received-date cannot be determined, the message-creation date is used.

More details about retention age for different types of items in "How Retention Periods Are Calculated for Items in Managed Folders".

You locate an older PST and copy a Calendar item which occurs in roughly the same timeframe as the one you just created. When you run the MFA, the copied item with an end date from more than a year ago is expired!

When processing a mailbox, the MFA queries for Calendar items where the creation date is older than the expiration date. If you create a test item for a past date, as we did in this case, it does not get processed by the MFA until the creation date is older than the AgeLimitForRetention.


Figure 3: Calendar items created for a past date will have a creation time that is later than the meeting/appointment end time

Of course, you're not likely to run into this issue except in test scenarios. Real-world meetings do not get created in the past. The creation date is guaranteed to be equal to or older than the end date of the meeting..