New Outlook Shared Mailboxes: AutoMapping, Sync and Notifications Explained

AutoMapping doesn't mean "appears as an account" anymore

In classic desktop Outlook, an AutoMapped shared mailbox shows up as its own top-level account in the folder pane, automatically. New Outlook for Windows does this differently: an AutoMapped mailbox lands under Shared with me instead, and the user has to click Convert to promote it to a full account. Source: Manage shared mailbox settings in new Outlook.

The underlying Exchange grant hasn't changed — Full Access with AutoMapping enabled is exactly the same server-side permission either client reads. What changed is how New Outlook chooses to surface it.

The Inbox doesn't sync until you convert it

This is the part that catches people off guard: Microsoft states directly that "incoming emails aren't automatically synchronized in the Inbox folders of shared mailboxes added by automapping." A delegate who never converts the mailbox can open it under Shared with me and see stale mail, because New Outlook isn't keeping it current in the background. Source: Sync a shared mailbox in new Outlook.

Two documented ways around it: manually trigger a sync (View → Sync, or select the folder), or click Convert to promote the mailbox to a full account, which restores automatic sync going forward.

Notifications, rules and automatic replies need the same conversion

Microsoft's shared-mailbox settings page lists categories, notifications, rules and automatic replies as supported for shared mailboxes — but in the context of the account selector, which means after the mailbox has been converted to a full account. We didn't find an official, numbered procedure for toggling notifications on an unconverted Shared-with-me mailbox specifically, so treat that as unsupported or at least undocumented rather than assuming a hidden setting exists.

What's still not there

Calendar-event search inside a shared mailbox is explicitly marked "Coming soon" on Microsoft's own page — email search inside a shared mailbox works, calendar search doesn't yet.

Permission state and client behavior are two different layers

Whether a delegate has access at all is a server-side Exchange decision — Full Access, Send As, Send on Behalf, and whether AutoMapping is set. Whether that access shows up as an automatic top-level account, a Shared-with-me item requiring manual sync, or a fully converted account with notifications working is client behavior layered on top, and New Outlook's layer works differently from classic Outlook's. Tenvero manages the first layer — the permission and the AutoMapping setting behind it — and doesn't change or fix how New Outlook chooses to sync or notify once that grant exists.