Around the beginning of February, Microsoft announced that they were retiring the Site Mailbox functionality in Exchange Online.
Back when Exchange 2013 was released, there was a lot of publicity about the Site Mailbox capability and how it would make it easier to collaborate between team members. In a nutshell, a Site Mailbox was a repository for both emails and documents, making them visible through the Outlook client.
In the years I have been working on Exchange, I can count the number of customers that have used Site Mailboxes on one hand and it’s to do with the way the data is stored. You see, emails are stored in Exchange 2013 whilst documents are held in SharePoint 2013 document libraries with a stub pointer in the mailbox.
In many cases, it’s that requirement for a SharePoint server that turned people away because they don’t have the resources to deploy and manage a resilient SharePoint farm alongside their new resilient Exchange platform.
This functionality will still exist in the on-premises Exchange 2013 and Exchange 2016 platforms; Microsoft have only removed the functionality for new Site Mailboxes within Office 365 although they will eventually remove the existing Site Mailboxes after tenants have moved to alternatives.
So what are the alternatives?
If the Site Mailbox is primarily being used for document collaboration, it’s recommended to move to SharePoint Team Sites and document libraries.
On the other hand, if the Site Mailbox is primarily being used for emails, it would be best to move to Shared Mailboxes or Office 365 Groups (however, Microsoft Teams has been released all Office 365 tenants so there’s a third option).
Within the risual UC team, we use Office 365 Groups quite heavily because of the integration between OneNote, Planner, OneDrive and Exchange. It makes a huge difference to how we communicate with each other and that will only improve further once Microsoft complete the integration of Yammer into Office 365 Groups.
My colleague Mark Wilson made an excellent post about the differences between Microsoft Teams and Office 365 Groups here which I recommend reading before you start making plans to retire Site Mailboxes.