How to E-Mail Merge from Shared Mailbox (Microsoft 365).
If you want to send a mail merge from a shared mailbox using Microsoft Word & Outlook, then this guide is for you.
A shared mailbox in Microsoft 365 (aka "Office 365") lets multiple users send and receive emails from a common address (e.g "sales@example.com") without needing a separate license. But, by default, Microsoft Word’s Mail Merge feature sends only from the default Outlook user account and not from shared mailbox. However, with the right setup in Office 365 & Outlook, you can send merged emails "From" a shared mailbox.
How to Send Mail Merge Messages from a Microsoft 365 Shared Mailbox in Outlook.
As you may know, when a mail merge is performed in Word, the emails are sent from the default email account in Outlook. This means that if you have more than one email account set up in Outlook (e.g. "email account A" and "email account B), and you want to do a mail merge from "email account B", you will need to set the "email account B" as the default account in Outlook before performing the mail merge.
The same applies when you have access to and want to perform mail merges from a shared mailbox' You must set the shared mailbox as the default account in Outlook after adding it as an additional email account.
However, an Office 365 shared mailbox usually cannot be added as an additional email account in Outlook, because by default it is automatically mapped to the regular email account of the user(s) who has delegation rights to it.
This happens because of the "Automapping" feature of Office 365 and Outlook, which is enabled by default in Office365 and forces the shared mailbox to automatically appear in the user's Outlook, without requiring any additional action/configuration on the user's part to have access to the shared mailbox.
To turn off the "Automapping" feature on a shared mailbox so you can add it as a regular account in Outlook and use it as the default account for mail merges, follow the steps below:
Step 1. Disable Shared Mailbox Automapping in Office365.*
To disable the Outlook Automapping of a shared mailbox, connect to Exchange Online through PowerShell, remove the user's full access permissions on the shared mailbox and then re-add the permissions with the "Automapping" feature disabled. To do that:
* Note: This step requires administrator privileges in Office 365.
1. Connect to Exchange online via PowerShell using your Office 365 admin credentials.
2. After connecting to Exchange Online, issue the below command to remove the user's full access permissions on the shared mailbox and then press "y" (YES) when asked to confirm your decision:*
- Remove-MailboxPermission -Identity SharedMailboxName -User UserName -AccessRights FullAccess
* Where:
- SharedMailboxName: is the name or email address of the Shared mailbox.
- UserName: is the name or email address of the person who has delegation rights on the Shared mailbox.
For example: If you want to remove the permissions of the User "helen@example.com" on the Shared Mailbox "sales@example.com", issue the following command:
- Remove-MailboxPermission -Identity sales@example.com -User helen@example.com -AccessRights FullAccess
3. Then reassign to the user the full access permissions on the Shared mailbox but with the "Automapping" feature disabled, with this command:*
- Add-MailboxPermission -Identity SharedMailboxName -User UserName -AccessRights FullAccess -AutoMapping $false
* Where:
- SharedMailboxName:: is the name or email address of the owner's mailbox.
- UserName: is the name or email address of the person who will have full access rights on the Shared mailbox, with the Outlook automapping Feature disabled.
For example: If you want to give permissions to the user "helen@example.com" on the Shared mailbox "sales@example.com" but with automapping disabled , issue the following command:
- Add-MailboxPermission -Identity sales@example.com -User helen@example.com -AccessRights FullAccess -AutoMapping $false
4. After running the above command you should receive a similar screen bellow:
5. Disconnect from Exchange Online and continue to next step.
Step 2. Add Shared Mailbox's Email Account as a New Account in Outlook.
1. Restart Outlook on the user's computer and verify that the Shared Mailbox is no longer automatically mapped (does not appear) in the Outlook folder pane.*
* Note: For this to happen, you may need to wait a while or restart the computer.
2. After you verify that the Shared mailbox is no longer appears in user's Outlook, add the account of the Shared mailbox as a new email account. To do this:
a. From File menu > go to Account Settings and click New.
b. In the next screen type the email address of the Shared Mailbox (e.g. "sales@example.com" in this example) and click Connect.
c. On the "Enter Password" screen, type the password for the shared mailbox email account and try to Sign in. If the login is unsuccessful because the password is incorrect, click Sign in with another account, and then type the credentials of the user (e.g. the "helen@example.com" in this example), who has delegation permissions to the shared mailbox.
3. Once the account is successfully added, restart Outlook to apply the change.
4. After restarting, the Shared Mailbox's email account will be added in Outlook's left navigation pane. Now, proceed to next step to learn how to mail merge from the shared mailbox.
Step 3. How to Mail Merge from the Shared Mailbox.
When you want to Mail Merge using the Shared Mailbox's account, do the following:
1. Close Word.
2. In Outlook go to File menu and open Account Settings.
3. In 'Email' tab, select the shared mailbox's email account and click Set as Default.
4. Then select to 'Data Files' tab, select the shared mailbox data file and click Set as Default again. When done, close Account Settings and restart Outlook.
5. Now open Word and perform the mail merge as you normally would. After sending the email messages, you will see that each message has been sent using the shared mailbox account and all sent messages are stored in the shared mailbox's "Sent Items" folder.
6. After you complete the mail merge, reopen Account Settings in Outlook and set both the user's email account and its data file as the default.
That's it! Let me know if this guide has helped you by leaving your comment about your experience. Please like and share this guide to help others.

