Microsoft plans to reduce the recovery period for inactive mailboxes newly released from retention holds and policies from 183 to 30 days. The change will be implemented worldwide by the end of September. The reduction in recovery time sounds seriously but it’s really not. If you haven’t figured out that you need to recover some data from an old inactive mailbox within 30 days, the data probably isn’t needed. And anyway, if you really want to, you can keep inactive mailboxes forever.
Exchange Online tenants have a choice between inactive mailboxes and shared mailboxes when the need arises to keep “leaver” data like that belonging to ex-employees. Inactive mailboxes are essentially a compliance tool and sometimes shared mailboxes are better choices. We explore both in this short article.
Most Microsoft 365 tenants will have to manage the mailboxes of ex-employees. Retention policies are an excellent method to achieve this goal, if you remember to add mailboxes to a suitable retention policy before deleting their Azure AD account. In this article, we consider Microsoft’s recommendation to use a specific retention policy for inactive mailboxes and how to go about using such a policy.
Inactive mailboxes have been available in Exchange Online since 2015. A new inactive mailboxes listing is available in the Microsoft 365 compliance center. The GUI isn’t very functional, but perhaps it’s a starting point for some enhanced management capabilities for inactive mailboxes. We’ve only been waiting six years…
Exchange Online supports inactive mailboxes as a way to keep mailbox data online after Office 365 accounts are removed. Inactive mailboxes are available as long as a hold exists on them. You can update mailbox properties to exclude all or some org-wide holds. If you exclude holds from a mailbox, you run the risk that Exchange will permanently remove the mailbox. If that’s what you want, all is well, but if it’s not, then you might not be so happy.