Use a Shared Mailbox in Outlook and Mail Apps

Suppose your team handles support@example.com. In Webmail, each member can open that inbox without a second login. The same arrangement works in Outlook, Apple Mail, Thunderbird, and other IMAP apps: connect your own mailbox, then open support@example.com under its delegated Shared folder.

There is no password for the shared address. Membership and the Can reply permission 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 password of that regular mailbox;
• 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:

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 Can reply 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

SMTP delivers the message but does not save a Sent copy. The mail app performs that separate IMAP operation. Configure the shared sending identity to save sent messages in:

Shared/<shared-address>/Sent

A member with Can reply 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

The account administrator changes this permission on the shared mailbox's Access tab. Removing a member revokes both the delegated IMAP folder and Send As permission.

With Can reply, 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 the regular mailbox address and its mailbox password, not 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 Can reply 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 and Can reply. 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.