Use a Shared Mailbox in Outlook and Mail Apps

With Read, connect your own mailbox to Outlook, Apple Mail, Thunderbird, or another IMAP app using your own address and an app password. Open the team inbox under Shared/<shared-address>/INBOX. Never sign in with the shared address.

There is no password, app password, or mail app sign-in mode for the shared address. Membership and the Read and Send as permissions decide what each person can do.

Before you start

You need:

• an active regular mailbox that has been added as a member of the shared mailbox;
• the full address and an app password for that regular mailbox, or its mailbox password if it still accepts it;
• the server settings shown in Webmail under Settings, Apps & devices.

If Apps & devices does not list your shared mailboxes, ask the account administrator to confirm your membership and whether native mail-app access is available for the service.

1. Connect your own mailbox

Add your regular mailbox to the app. Always use the values shown in Apps & devices; the standard secure settings are:

Use the hosts shown for your mailbox. A White Label service can use its own server names; the example hosts below are not a substitute for your settings.

Create an app password for your regular mailbox in webmail under Settings, App passwords, or ask an admin to create one under Mailboxes, (your mailbox), Security, App passwords. App passwords only requires it; Mailbox password or app passwords accepts either. See Mail app passwords.

Do not add the shared address as another account. Direct sign-in to a shared mailbox is intentionally disabled.

2. Find the shared inbox

The server attempts the membership update immediately and retries pending work every minute. In Apps & devices, wait until the shared mailbox says that mail-app access is active. Then expand Shared and open:

Shared/<shared-address>/INBOX

For support@example.com, the server path is:

Shared/support@example.com/INBOX

An app may display that as Shared, support@example.com, Inbox. The server adds the initial subscription, but an app that was already open may keep an old folder list. Refresh its folders or reconnect; if necessary, use its folder-subscription screen.

3. Send from the shared address

Members with Read and Send as permission may use the shared address in the message's From field. The SMTP username and password must still belong to the member's regular mailbox.

If the app does not offer the shared address in its From list, add it as a sending identity or alias on the existing account. Do not create a second IMAP account for it.

Keep replies and forwards in the shared Sent folder

With Read and Send as, configure the shared sending address to save copies in the shared Sent folder. SMTP delivers the message but does not save a Sent copy; the mail app does that separately. Only people with both permissions can save copies in:

Shared/<shared-address>/Sent

A member with Read + Send as may create that folder if it does not exist. If the app saves the copy in the member's personal Sent folder instead, the message was still sent, but other team members will not see the copy in the shared mailbox.

What the permissions allow

Read opens the shared inbox. Send as allows sending as its address. New people receive both permissions. Leave Read on and turn Send as off for read-only access. Removing someone takes effect immediately. At least one person must keep Read to handle customer replies. Give another person Read before removing the last reader. If nobody can read the inbox after a member mailbox is deleted, add a reader on Access.

With Read + Send as, ordinary IMAP actions work inside the shared tree: mark read or starred, create folders, archive, move, copy, delete, and expunge. Messages can also move or copy between personal and shared folders. Choose Shared/<shared-address>/Archive or Shared/<shared-address>/Junk manually if the app does not map its Archive or Spam button to those folders.

Moving a message to the shared Junk folder is a folder operation. It does not promise that the server's spam classifier was trained; use Webmail's Report spam action when classifier training is required. Likewise, forwarding a message from a mail app is different from configuring automatic mailbox forwarding in the dashboard.

If something does not work

• The shared folder is missing: Confirm membership first, then refresh or subscribe to the app's IMAP folders.
• Authentication fails: Sign in with your regular mailbox address and an app password, or its mailbox password if accepted. If the app says "Sign-in failed. This mailbox accepts app passwords only: create one in webmail under Settings > App passwords.", create an app password for your regular mailbox. Never use the shared address or dashboard password.
• Messages open but cannot be changed: The membership is read-only.
• The app rejects Send As: Authenticate SMTP with the regular mailbox, select the shared address only in From, and confirm Send as is still enabled.
• A sent reply is missing from the team mailbox: Set that identity's Sent folder to Shared/<shared-address>/Sent; sending and saving the copy are separate operations.
• Access was recently changed: Reconnect or resynchronize the app so it reloads the current folder and sending permissions.

For administrators and automation

The shared mailbox's Access tab is the source of truth for membership, Read, and Send as. Manage access there rather than through server-level settings.

API clients can request:

GET /api/v1/mailboxes/{member_mailbox_id}/client-setup

MCP clients use get_mail_client_setup with the regular member mailbox id. The shared_mailboxes object returns durable readiness, exact Inbox/Sent/Archive/Junk paths, server-enforced operations, and the allowed Send As address. Wait for native_access_ready=true and send_as_ready=true before guiding a user through full read-and-send setup. Neither interface returns a password.