Overview
Shared mailboxes are used when multiple people need access to the same mailbox, such as an info@ or support@ email address that might be shared by multiple people.
Users with permission to the group mailbox can send as or send on behalf of the mailbox email address if the administrator has given that user permission to do that.
Sign in with a Global admin account or Exchange admin account. If you get the message “You don’t have permission to access this page or perform this action,” then you aren’t an admin and will be unable to create a shared mailbox
In the admin centre, go to the Teams & Groups > Shared mailboxes page.
On the Shared mailboxes page, select + Add a shared mailbox. Enter a name for the shared mailbox. The chooses the email address, but you can edit it if needed.
Select Save changes. (This can take up to 5 minutes before you can add members.)
Select the Shared Mailbox you wish to add Users to.
Select edit under Members.
Here you can add users to your Shared Mailbox. All users need to be licenced in order to access shared mailboxes.
You can use the following permissions with a shared mailbox:
Full Access: Read and Manage permissions are called Full Access permission when granted in the Exchange admin centre. Full Access permission does not grant Send as or Send on Behalf permissions.
Send As: The Send As permission lets a user impersonate the shared mailbox when sending mail.
Send On Behalf: The Send on Behalf permission lets a user send an email on behalf of the shared mailbox. ( Appears as email name on behalf of shared mailbox name)
Now you can add Permissions to the users of your New shared mailbox. Read and Manage (Full Access), Send As and Send On Behalf permissions.
Select Read and Manage Permissions, here you can set the permissions for users that can read, send as, or send on behalf of this shared mailbox.
Select Add permissions then add the required user.
Once all the required users are added hit save.