Guides / Shared mailbox not showing in Outlook

Part of: Email not sending, receiving or syncing

Last reviewed 6 Oct 2026 · By Harry

Shared mailbox not showing in Outlook

Shared mailbox missing from the folder pane, not updating, or sent items landing in the wrong place? Permissions, automapping and Outlook fixes.

The admin says I gave you access an hour ago. The user says it's not there. Or the shared mailbox appears but has not updated since Tuesday. Or emails sent from the shared address land in the user's own Sent Items. Shared mailbox tickets are almost always permissions timing, automapping, or Outlook caching — and they are worth getting right because they usually involve a team inbox like accounts@ or support@.

Prove the permission works

In Outlook on the web, click the profile picture → Open another mailbox, type the shared mailbox address, and open it. If that works, Exchange Online has granted access and the desktop client needs attention. If it fails with an access error, the permission is missing or has not replicated yet. Microsoft notes that permission changes can take time to take effect — up to an hour is normal, longer is worth checking.

Only check the Outlook status page if many users lose shared mailboxes at once; a single missing mailbox is never an outage.

Admin: grant the right permissions

• Full Access lets the user open and read the mailbox. Grant it in the Microsoft 365 admin centre (Teams & groups → Shared mailboxes) or the Exchange admin centre.
• Send As lets them send as the shared address. Send on Behalf shows "user on behalf of mailbox". Pick one; users often have Full Access but cannot send because nobody granted Send As.
• Automapping. When Full Access is granted through the admin centre, Outlook desktop adds the mailbox automatically after a restart and the autodiscover refresh. When granted with PowerShell and -AutoMapping $false, or through a security group, it will not appear automatically — the user must add it manually.
• Groups do not automap. Full Access via a mail-enabled security group works but does not automap. Either add it manually per user or grant direct permissions.

User: add or refresh the mailbox in Outlook

1. Restart Outlook after the permission has had time to apply. Automapped mailboxes appear on the next autodiscover cycle.
2. Add it manually (classic Outlook): File → Account Settings → Account Settings → select your account → Change → More Settings → Advanced → Add, then type the shared mailbox name. Alternatively add it as a second account if you need separate Sent Items and rules — this needs a licence on some setups, so check with IT.
3. New Outlook for Windows: right-click Shared with me in the folder pane → Add shared folder or mailbox.
4. Mailbox not updating. Shared mailboxes are cached by default in classic Outlook. If one is stale, try turning off Download shared folders in the Cached Exchange settings, restart Outlook, and test. Large shared mailboxes can also stall the whole OST — a new profile is the next step.
5. Sent items in the wrong place. By default, mail sent as the shared mailbox may be saved to the sender's Sent Items. Admins can enable copying sent items to the shared mailbox's Sent Items using Exchange Online PowerShell (Set-Mailbox -MessageCopyForSentAsEnabled $true and the SendOnBehalf equivalent).

Removing access that will not go away

If a leaver's shared mailbox stays in someone's Outlook after access was removed, it is usually automapping metadata. Remove the permission, wait, restart Outlook. If it persists, remove and re-grant Full Access with automapping disabled, then remove it again, or create a new Outlook profile.

Other causes worth checking

• Hybrid Exchange. Cross-premises shared mailbox permissions between on-premises and Exchange Online have limitations. Move both the user and the shared mailbox to the same side where possible.
• Mobile. Outlook mobile supports adding shared mailboxes from the account settings, but only when Full Access is granted directly. Native mail apps generally do not.
• Licences and size. Shared mailboxes are unlicensed up to a size limit; beyond that, or with an archive or litigation hold, they need a licence. A full mailbox stops receiving mail, which users report as "not working".

When to escalate

Escalate to Microsoft when many shared mailboxes disappear tenant-wide and Service health shows an Exchange advisory. Otherwise this is an admin and Outlook-client task: confirm access in OWA, fix the permission type, then refresh or rebuild the Outlook profile.

Related status pages

• Outlook
• Microsoft 365
• Microsoft Entra ID

Related guides

• Outlook search not working or returning no results
• Outlook disconnected or not syncing: is it Microsoft or you?
• Outlook keeps asking for a password: how to stop the prompts

FAQ

Why is my shared mailbox not showing in Outlook?

The permission may still be applying, automapping may be off (for example when access comes from a group), or Outlook needs a restart. Test in Outlook on the web with Open another mailbox.

How long do shared mailbox permissions take?

Often minutes, but it can take up to about an hour for changes to apply. Restart Outlook afterwards so autodiscover picks up automapped mailboxes.

Why can I read the shared mailbox but not send from it?

Full Access only allows reading. An admin must also grant Send As or Send on Behalf for you to send from the shared address.

Why do emails I send from the shared mailbox go to my Sent Items?

That is the default. An admin can enable saving a copy to the shared mailbox Sent Items with Exchange Online PowerShell.