Permission & Access Issues

How to Assign Exchange Online Shared Mailbox Access to a Group

Huma Ashraf Ch Sep 28, 2026 869 views

Question details

The user needs to assign shared mailbox permissions such as Full Access, Send As, or Send on Behalf to a group of users in Exchange Online.

How to Assign Exchange Online Shared Mailbox Access to a Group

Product: Microsoft Exchange Online
Device & OS: not provided
Scenario: Managing and granting access to shared mailboxes for multiple users within a Microsoft 365 environment.
Observed behavior: Exchange Online does not allow assigning mailbox permissions directly to distribution lists; a security group must be used instead.

Before you start

Ensure you have Exchange Administrator privileges in Microsoft 365 and that you have the Exchange Online PowerShell module installed and ready to connect.

Solution 1Recommended

Use a Security Group and Exchange Online PowerShell

The correct and supported method to assign shared mailbox permissions to multiple users is by utilizing a mail-enabled security group via PowerShell.

Because distribution lists and shared mailboxes cannot act as direct permission principals in Exchange Online, you must set up a security group or mail-enabled security group to handle bulk access assignments effectively.

Create a security group

Log in to the Microsoft 365 admin center, navigate to Teams & groups > Active teams and groups, and create a new Mail-enabled security group. Add all the required users as members of this group.

Connect to Exchange Online PowerShell

Open PowerShell on your computer as an administrator and run the command 'Connect-ExchangeOnline' to authenticate with your Microsoft 365 admin credentials.

Assign Full Access permissions

Run the Add-MailboxPermission cmdlet to grant the security group access. For example: Add-MailboxPermission -Identity "sharedmailbox@yourdomain.com" -User "securitygroup@yourdomain.com" -AccessRights FullAccess -InheritanceType All.

Assign Send As permissions

If the group also needs to send emails from the shared mailbox, run the Add-RecipientPermission cmdlet: Add-RecipientPermission -Identity "sharedmailbox@yourdomain.com" -Trustee "securitygroup@yourdomain.com" -AccessRights SendAs.

Use a Security Group and Exchange Online PowerShell

Service Request for Bulk Configurations: If you are managing a very large enterprise environment and need assistance with bulk configuration of these permissions, you can create a service request in the Microsoft 365 admin center under Support > Service requests.

Free Microsoft Office alternative

Looking for a Lightweight Office Suite Alternative?

While you manage your Exchange and Microsoft 365 administrative tasks, consider WPS Office as a free, lightweight, and highly compatible alternative for your organization's daily document creation and editing needs.

1. Download the installer: Visit the official WPS Office website and click on the Free Download button.
2. Install the software: Run the downloaded installer and follow the quick on-screen instructions to set up WPS Office on your device.
3. Open your documents: Launch WPS Office and instantly open, edit, or save your existing .docx, .xlsx, and .pptx files without formatting issues.

Fully compatible with Microsoft Word, Excel, and PowerPoint formats.Free and lightweight, consuming significantly fewer system resources.Familiar user interface for a seamless migration with zero learning curve.Built-in PDF editing tools for comprehensive document management.

microsoft office alternative - wps office

Frequently Asked Questions

Can I assign shared mailbox permissions directly to a distribution list?

No, Exchange Online does not support assigning mailbox permissions such as Full Access or Send As to standard distribution lists. You must use a security group or a mail-enabled security group instead.

How long does it take for shared mailbox permissions to apply to group members?

After assigning permissions via Exchange Online PowerShell, it can take up to 60 minutes for the new access rights to fully propagate and for the shared mailbox to appear in the users' Outlook clients.

How do I assign 'Send on Behalf' permissions to a group?

To assign Send on Behalf permissions, you need to use the Set-Mailbox cmdlet in PowerShell with the -GrantSendOnBehalfTo parameter, specifying your mail-enabled security group as the value.

Document & File Issues