Shared Mailbox in Outlook: How to Add It on Windows and Mac

To add a shared mailbox in Outlook, first make sure your Microsoft 365 or Exchange administrator has granted your account access, then add the mailbox in Outlook or wait for it to appear automatically. A shared mailbox lets a team read and manage messages from one address; you generally use your own work account to open it, not a separate shared-mailbox password.

What You’ll Need

Permission to access the mailbox. Ask your Microsoft 365 or Exchange administrator for Full Access permission. Being able to open a mailbox does not automatically give you permission to send from its address; ask for Send As or Send on behalf permission too if you need to reply as the team.
The shared mailbox’s email address. Get the exact address, such as support@company.com, from its owner or your administrator. A display name may not be enough to identify the right mailbox.
An Outlook account connected to your organization. Sign in with the work or school account to which the permission was assigned. A personal Outlook.com account normally cannot open an organization’s Exchange shared mailbox just by knowing its address.
A supported Outlook app and an internet connection. The labels and menus vary between classic Outlook, new Outlook, and Outlook for Mac, so identify which app you are using before following the steps.

Step-by-Step

Confirm access and identify your Outlook version. Ask the mailbox owner or IT administrator to confirm that Full Access has been assigned to your work account. On Windows, classic Outlook has a File tab in its ribbon; new Outlook has a modern interface and a settings gear. On a Mac, use the Outlook app for macOS and follow the Mac-specific step below. If permission was just granted, it may take a little while to become active.
Check whether Outlook added the mailbox automatically. Close and reopen Outlook, then look in the folder pane on the left. A mailbox with Full Access is often added automatically by Exchange. Expand the mailbox name or its folders if it is collapsed. If it is already there, open its Inbox and check that you can see messages; adding it again may create a duplicate entry.
Add it in new Outlook for Windows if it is missing. In the Mail view, find Shared with me in the folder pane. Right-click Shared with me (or the relevant account or folder area if your build presents a different layout), select Add shared folder or mailbox, and enter the shared mailbox’s full email address. Select the matching result, then choose Add. The mailbox should appear in the folder pane, where you can expand it to open its Inbox, Sent Items, and other available folders. In some builds, the option is also available under Settings > Accounts > Shared with me.
Add it manually in classic Outlook for Windows if it is missing. Select File > Account Settings > Account Settings. On the Email tab, select your Microsoft 365 or Exchange account and choose Change. Select More Settings, open the Advanced tab, and choose Add under the section for additional mailboxes. Enter the shared mailbox’s email address and select OK. Select Apply and OK to close the settings windows, then select Next or Finish if Outlook shows that option. Restart Outlook and look in the folder pane. Menu labels can differ slightly by Outlook build, but this route applies to classic Outlook connected to Exchange.
Add it in Outlook for Mac if it is missing. In Outlook, open Tools > Accounts (in some versions, use Outlook > Settings > Accounts). Select your work account, then open Delegation and Sharing or Delegation & Sharing. Choose the Shared With Me tab, select the plus button, and enter the mailbox address. Select the matching mailbox and add it. Close the settings and check the folder list. If your version does not show these controls, update Outlook or ask your administrator which Mac setup route your organization supports.
Open the mailbox and verify the right folders. In the folder pane, expand the shared mailbox name and select its Inbox. Depending on your access and the mailbox configuration, you may also see folders such as Drafts, Sent Items, or Archive. If you only need to read or organize messages, Full Access may be sufficient. Do not assume that seeing the mailbox means you can send from it.
Send a test message only if you have sending permission. Create a new message and show the From field if it is hidden. In classic Outlook for Windows, use Options > From; in new Outlook, use Options > Show From when available. In Outlook for Mac, use the message’s From field or its sender menu. Select the shared address, address a brief test to an appropriate colleague, and check the sent message’s sender. If Outlook rejects the address, ask IT to confirm Send As or Send on behalf permission rather than repeatedly retrying.

Common Mistakes

Trying to sign in with the shared address. Shared mailboxes are normally opened through your own organizational account. They are not usually intended for direct sign-in, and asking for or using a shared password is not the right setup. Use your assigned account and have IT grant access to it.
Assuming access includes permission to send. Full Access lets you open and manage the mailbox, but it does not by itself grant Send As or Send on behalf rights. Get the specific sending permission you need before composing messages from the shared address.
Adding the mailbox before access is assigned. Typing an address into Outlook does not grant access. If the mailbox cannot be found or added, confirm that the administrator assigned permission to the exact account you are signed in with.
Adding it twice when it is already mapped. Exchange may add a mailbox automatically after permission is granted. Check the folder pane and restart Outlook before using a manual add route. If duplicate entries appear, ask IT which one to keep before removing account settings.
Following instructions for the wrong Outlook app. The classic Windows Advanced tab steps do not match the new Outlook interface, and Mac menus differ from Windows. Check for the File tab or Settings gear first, then use the matching instructions.

Tips

Use the full email address when adding it. This helps Outlook resolve the intended mailbox, particularly when your organization has several mailboxes with similar names.
Allow time for permissions to take effect. A new permission may not appear instantly on every device. After IT confirms the change, restart Outlook and allow time for Exchange to update before trying again.
Keep personal and shared messages distinct. Before sending, check the From field and the recipient list. A message sent from your own address may reach the same recipients but will not appear to come from the shared team address.
Agree on how the team handles messages. Coordinate who replies, which folder holds completed work, and whether messages should be marked read. Shared mailbox changes can be visible to other users, so a simple team convention helps prevent duplicate replies.
Use the mailbox’s Sent Items carefully. Depending on how Exchange is configured, messages sent as the shared address may or may not be copied to the shared mailbox’s Sent Items folder. If colleagues need a shared record, ask IT whether sent-item copies are enabled for the mailbox.
Prefer Outlook’s supported mailbox controls over workarounds. Do not add the shared mailbox as an unrelated personal account or change your organization’s sign-in settings to make it appear. If the normal add options are unavailable, your administrator can check the Exchange configuration.

Troubleshooting

The mailbox does not appear after you add it. First confirm that you are signed into the work account that received Full Access. Check the folder pane for a collapsed mailbox and restart Outlook. If it remains missing, ask IT to verify the permission, the mailbox address, and whether the access change has had time to propagate. In classic Outlook, close and reopen the app after applying the Advanced tab change.

Outlook says the mailbox cannot be found or added. Re-enter the full address and check for spelling errors. The address may be an alias, or the item selected from search may not be the mailbox you were given. Ask the mailbox owner or IT for the primary email address and confirm that your account has permission. If the address is correct but still cannot be resolved, the issue may require an administrator to check the Exchange mailbox.

You can open messages but cannot send from the shared address. This usually means you have access to open the mailbox but lack Send As or Send on behalf permission, or that the From field is set to your own account. Ask IT which sending permission is intended, wait for it to take effect, then select the shared address in From. If the message sends but shows your name on behalf of the mailbox, that may be expected when you have Send on behalf rather than Send As.

You receive an access-denied message or a password prompt. Do not enter a guessed shared-mailbox password or repeatedly try different credentials. Confirm that Outlook is connected to your organization and signed in with the account granted access. Then contact IT with the exact error text and the mailbox address; an administrator can check permissions and sign-in configuration.

Messages or folders seem missing. Make sure you opened the shared mailbox’s Inbox rather than your personal Inbox, and expand the correct mailbox in the folder pane. Look for other folders, such as Archive, if the team uses them. If a folder is still absent, ask the mailbox owner whether it exists and whether you have access; a view or synchronization delay can also make recent changes take time to show.

The Mac or Windows menus do not match these steps. Outlook interfaces change over time, and classic and new Outlook do not share all the same commands. Confirm which version you have, install available Office updates if your organization allows it, and use the corresponding add-mailbox method. If your app has no shared-mailbox control, provide IT with your Outlook version and operating system so they can give the supported route.

Frequently Asked Questions

Do I need a separate password for a shared mailbox?
No, in the usual Microsoft 365 setup you open it using your own work account after an administrator grants access. Do not request or use a shared password unless your organization has explicitly documented a different, approved setup.

Why did the shared mailbox appear automatically?
Exchange can automatically map a mailbox to Outlook when Full Access is granted. Restart Outlook and check the folder pane before adding it manually. Automatic appearance is normal and does not indicate that you need to sign in separately.

Can I add a shared mailbox if I only have its email address?
Not unless your account has permission. The address identifies the mailbox, but it does not grant access. Ask the mailbox owner or administrator to assign the appropriate rights to your work account.

Can I send email from the shared mailbox?
Yes, if an administrator has granted Send As or Send on behalf permission. Full Access alone is not enough. Use the From field to select the shared address, and check the displayed sender before sending.

Will the mailbox appear on my other devices?
It may, if you sign into Outlook on those devices with the same organization account and your organization supports shared mailboxes there. If it does not appear, use the relevant app’s shared-mailbox option or ask IT; desktop setup does not guarantee that every mobile or web app will show it immediately.

Can I remove it later?
Usually, yes. Remove a mailbox you added manually using the relevant Outlook account or shared-mailbox settings. If Exchange added it automatically, removing it locally may not last while you still have Full Access; ask IT or the mailbox owner to remove your permission if you no longer need access.

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