A shared mailbox is a mailbox that shared by multiple members. The members have their own accounts with Microsoft 365. Member of a shared mailbox can read and optionally send email messages from the shared mailbox. Shared mailboxes also provide a common calendar, allowing members to schedule and view appointment, vacations and other work.
Shared mailboxes currently do not require a license and are therefore free for Microsoft 365 (April 2024). However, cloud-based backup and management services for shared mailboxes are charged by your technology provider.
Good practice suggests that members without a Microsoft 365 license should not be given access to shared mailboxes. Therefore, we do not encourage clients create and distribute passwords for shared mailboxes. Instead, each member must have their own Microsoft 365 license.
Important: Before you can use a shared mailbox, you must be added as a member and given the appropriate permission.
Adding a shared mailbox to Outlook on the web
Outlook on the web is the recommended method of opening shared mailboxes from external companies. We suggest starting with a private or incognito windows in your preferred browser. Using a private or incognito browser avoids conflicting and confusing security settings issued by Microsoft.
For more information: https://support.microsoft.com/en-au/office/open-and-use-a-shared-mailbox-in-outlook-on-the-web-98b5a90d-4e38-415d-a030-f09a4cd28207
Adding a shared mailbox to Outlook on the desktop
Outlook for the desktop (or Outlook client) is the preferred email management tool for many people. However it is important to appreciate all email messages from all individual and shared mailboxes will be syntonised onto your computer. This takes computing power, internet access, disk space and is less secure than using the web. We recommend you add only necessary and regularly accessed accounts.
For more information: https://support.microsoft.com/en-au/office/open-and-use-a-shared-mailbox-in-outlook-d94a8e9e-21f1-4240-808b-de9c9c088afd