Restrict Users sending email to Distribution Group

OFFICE 365

6/19/20221 min read

Exchange 2016/2019 (On-Premises) / Office 365

  1. Open the Exchange Admin Center (EAC):

    • Open a web browser and navigate to the Exchange Admin Center (EAC) for your Exchange 2019 server (typically https://<ExchangeServer>/ecp)

    • Log in with an account that has administrative privileges.

  2. Go to the Recipients Section:

    • In the left-hand menu, click on Recipients.

    • Then click on Groups to see the list of distribution groups.

  3. Select the Distribution Group:

    • Find and click on the distribution group that you want to configure.

  4. Edit the Group Settings:

    • In the distribution group properties page, go to the message delivery restrictions section.

    • Under Delivery Management, select Only senders in the following list.

      • This option allows only specific senders to send emails to the group.

  5. Add Allowed Senders:

    • Click on + (Add) and select users or groups who should be allowed to send messages to the distribution group.

    • Click Save to apply the changes.

  6. Block All Other Users:

    • If you want to block all users from sending emails to the distribution group except those you've specified, make sure Only senders in the following list is selected, and no other users are added.

    • Save the changes.

Using Exchange PowerShell

PS Command to Set Allowed Users to Send Email to Distribution Group

Set-DistributionGroup "All Users" –AcceptMessagesOnlyFrom user1@josephludwig.com, user2@josephludwig.com

To Verify:

Get-Distributiongroup -Identity "All Users" | FL AcceptMessagesOnlyFrom

PS Command to Add Allowed Users to Send Email to Distribution Group

Set-DistributionGroup "All Users" –AcceptMessagesOnlyFrom @{add="user3@josephludwig.com, user4@josephludwig.com"}

PS Command to Remove Allowed Users to Send Email to Distribution Group

Set-DistributionGroup "All Users" –AcceptMessagesOnlyFrom @{remove="user3@josephludwig.com, user4@josephludwig.com"}

Note:

  • If you need more complex restrictions (e.g., blocking users based on certain criteria), you can create a mail flow rule (transport rule):

    • In the Exchange Admin Center, go to Mail Flow > Rules.

    • Click + to create a new rule.

    • Set the conditions to restrict who can send emails to the distribution group.

    • Set actions to Reject the message with an explanation or Delete the message.

    That’s it! By following these steps, you should be able to restrict users from sending email to the Distribution Group.