Shared mailbox not showing

Summary

This guide helps you troubleshoot and resolve: Shared mailbox not showing. Follow the steps below to fix the issue.

Common Causes

Overview

Shared mailboxes allow multiple people to access a common email account, such as [email protected], without requiring a separate user licence. If a shared mailbox is not appearing in Outlook, follow this guide to add it and resolve common issues.

Before You Begin

Verify that the shared mailbox exists in Exchange Online and that your user account has been granted the appropriate permissions. Permission changes can take 15 to 30 minutes to propagate throughout Exchange. If you have just been granted access, wait at least 30 minutes before troubleshooting further.

Add Shared Mailbox in Outlook Desktop

Method 1: Automatic Appearance

When your IT administrator assigns you permissions to a shared mailbox, it should appear automatically after you restart Outlook.

1. Close Outlook completely.
2. Wait at least 30 minutes if permissions were recently granted.
3. Re-open Outlook.
4. Check the folder pane on the left for the shared mailbox.

Method 2: Manual Add via Folder Pane

Use this method if you have been granted access but the mailbox is not visible.

1. Right-click your primary email account name in the folder pane.
2. Select Add shared folder….
3. Enter the email address of the shared mailbox.
4. Click Add.
5. The shared mailbox will appear beneath your primary account in the folder pane.

Method 3: Account Settings (Outlook for Microsoft 365)

1. Go to File → Account Settings → Account Settings.
2. Select your Microsoft 365 email account from the list and click Change.
3. In the Change Account dialog, click More Settings.
4. Choose the Advanced tab.
5. Under “Open these additional mailboxes”, click Add….
6. Enter the shared mailbox email address and click OK.
7. Click OK, then Next, and finally Finish.
8. Restart Outlook.

Add Shared Mailbox in Outlook on the Web

1. Open outlook.office.com and sign in with your Microsoft 365 credentials.
2. Right-click your name or primary email address in the folder pane on the left.
3. Select Add shared folder from the context menu.
4. Alternatively, click the app launcher (waffle icon) in the top-left corner, select Outlook, then choose Open another mailbox.
5. Search for the shared mailbox name or email address.
6. Select the mailbox from the results and click Add.
7. The shared mailbox will appear under the Folders section.

Mobile Access

The Outlook mobile app for iOS and Android does not support adding a shared mailbox directly through Settings. There is no “Add shared mailbox” option in the mobile app.

To access a shared mailbox on a mobile device:

• Use Outlook on the web via your mobile browser and sign in to outlook.office.com.
• Alternatively, add the shared mailbox as a separate Exchange account in the Outlook mobile app if you have full access credentials and the mailbox is licensed.

Troubleshooting

Shared Mailbox Still Not Appearing

1. Verify permissions
   • Confirm with your IT administrator that you have at least “Reader” or “Full Access” permissions to the shared mailbox.
   • Ensure the shared mailbox exists and is active in Exchange Online.
2. Refresh folders
   • In Outlook desktop, right-click your account in the folder pane and choose Refresh Folders, or press F9.
   • In Outlook on the web, refresh the browser page.
3. Restart Outlook
   • Close Outlook completely and re-open it to force a synchronisation with Exchange Online.
4. Address Cached Exchange Mode issues
   • Go to File → Account Settings → Account Settings.
   • Select your Microsoft 365 account and click Change.
   • Under Offline Settings, clear the checkbox for Use Cached Exchange Mode.
   • Click Next, then Finish, and restart Outlook.
   • If the mailbox appears, you can re-enable Cached Exchange Mode. If problems persist, your Offline Storage Table (.ost) file may be corrupt. Close Outlook, rename or delete the .ost file (typically located in %localappdata%\Microsoft\Outlook), then restart Outlook to recreate it.

Send As vs Send on Behalf

Understand the difference between these two permissions before sending email from a shared mailbox:

Sent Items Behaviour

By default, messages sent from a shared mailbox are saved in your personal Sent Items folder, not in the shared mailbox’s Sent Items folder. To change this behaviour:

• An administrator can configure the shared mailbox in Exchange Online to copy sent items to the shared mailbox’s Sent Items folder.
• Alternatively, a registry key can be applied on the Outlook client to store sent items in the shared mailbox. This requires IT deployment and should be requested via a support ticket.

Licensing Information

Shared mailboxes in Microsoft 365 are free and do not require a licence if they are under 50 GB. If a shared mailbox exceeds 50 GB, it must be assigned a Microsoft 365 licence to continue functioning. If a shared mailbox has disappeared or stopped receiving mail, check with your administrator whether the mailbox has exceeded this size limit and requires a licence.

Common Issues

Need More Help?

Open a ticket with IT support and include:

• The shared mailbox email address.
• Your Microsoft 365 email address.
• Confirmation that permissions have been granted.
• Whether you are using Outlook desktop, Outlook on the web, or a mobile device.

For additional guidance, see How to add email to Outlook.

Open a Ticket

Still Having Issues?