Accessing a Microsoft 365 shared mailbox from main email applications like Outlook, Apple Mail, or mobile apps depends on the platform you’re using. Here’s a breakdown for the most common ones:

✅ Outlook for Windows or Mac (Desktop App)

Automatic Access (if you’re granted full access)

  1. Open Outlook.
  2. The shared mailbox should appear automatically in your folder pane.
    • If not, restart Outlook.

Manual Add (if it doesn’t show up)

  1. Go to File > Account Settings > Account Settings.
  2. Select your account and click Change.
  3. Click More Settings > Advanced tab.
  4. Under Open these additional mailboxes, click Add.
  5. Type the name of the shared mailbox and click OK.

✅ Outlook on the Web (OWA)

  1. Go to https://outlook.office.com .
  2. Sign in with your main account.
  3. In the left pane, right-click Folders > Add shared folder.
  4. Enter the shared mailbox name or email address.
  5. Click Add.

✅ Outlook Mobile App (iOS/Android)

Shared mailboxes cannot be added directly like a normal account. Instead:

  1. Open the Outlook app.
  2. Tap your profile icon > Settings.
  3. Tap your main account > Add Shared Mailbox.
  4. Enter the shared mailbox address.

✅ Apple Mail (macOS/iOS)

  1. Go to Settings > Passwords & Accounts.
  2. Click Add Account.
  3. Select Other.
  4. On the Other screen, touch Add Mail Account.
  5. In the new screen, you will enter:
    • Name: The name that will be displayed to recipients on email (District Chair).
    • Email: The email address of the shared mailbox (e.g., your-name@horshamscouts.com).
    • Password: Your email password.
    • Description: Your chosen description.
  6. Touch Next to get to the full settings.
  7. On the following screen, confirm that IMAP is selected at the top.
  8. Scroll down. In the Incoming Mail Server section, enter the following values:
    • Host Name: outlook.office365.com
    • User Name: Your personal email address, followed by a forward slash, followed by the name of the shared mailbox. For example, your-name@horshamscouts.com
    • Password: Your email password.
  9. Scroll down. In the Outgoing Mail Server section, enter the following values:
    • Host Name: smtp.office365.com
    • User Name: your-name@horshamscouts.com.
    • Password: Your email password.
  10. Touch the Next button and wait for the server to verify your settings.
  11. Choose your synchronization choices and touch Save in the upper right corner. You will now find the shared account in your Mail app under Mailboxes.

✅ Other IMAP Clients (e.g., Thunderbird)

Shared mailboxes are not directly supported unless:

  • You have login credentials for the shared mailbox.
  • Or you use a workaround like delegated access via IMAP, which is complex and not always reliable.