In March 2017, we took the first step towards deprecating site mailboxes by announcing that we will stop the creation of new ones. Today you can no longer create site mailboxes and over time we will stop support for the product completely.
Site mailboxes offered a great way to augment the collaboration options available on a SharePoint site. Despite people turning to site mailboxes to satisfy their email based collaboration needs, we have not seen the level of adoption that we would have liked. We have in fact, seen a declining trend over the years despite our best efforts to promote site mailboxes. To the customers who did use site mailboxes regularly, we appreciate your commitment towards our product and value your partnership. We understand that this decision will be disappointing for a few of you. But after a lot of internal deliberation, we have decided to deprecate site mailboxes and invest in Office 365 groups.
Office 365 groups go beyond just providing a shared inbox space by having a shared documents library, a shared calendar, a shared notebook and a lot more. See Learn about Office 365 Groups to know more. Groups are self-served and give more power to end users to actively collaborate among themselves. Whether you want to set up a small project team or a large helpdesk, Office 365 groups work great in all scenarios. In its short duration of existence, groups have already seen a much larger adoption than site mailboxes. This, coupled with the ability to associate a group with a SharePoint team site make Office 365 groups the ideal replacement for site mailboxes.
We understand that we have a lot of customers still actively using site mailboxes and that this deprecation will affect their day to day operations. We assure such customers that we are working on providing a solution for the transition process. By the end of 2017 we will have a process in place which will let you connect your classic experience SharePoint team site to an Office 365 group. As a start, you can check out Use Office 365 Groups instead of Site Mailboxes to know how to move to groups.
We are grateful for the continued patronage our customers have shown us and we hope to extend this into the future as well. Do reach out to us if you have any questions or concerns.