Applies to: Exchange Server 2010 SP3

Topic Last Modified: 2012-05-23

In a hybrid deployment environment between Microsoft Exchange Online and on-premises Microsoft Exchange organizations, the Microsoft Online Services Directory Synchronization Tool (DirSync) cannot be used to synchronize dynamic distribution groups to Exchange Online. Therefore, mailboxes that have been moved to Exchange Online cannot send mail to dynamic distribution lists. To work around this issue, create a contact in Exchange Online for the dynamic distribution list, and then grant permissions so that only authenticated senders can submit messages to the new contact.

Looking for other management tasks related to Managing Distribution Groups? Check out Managing Distribution Groups.

Looking for more information about hybrid deployments? Check out Hybrid Deployments.


  • Hybrid deployment between an on-premises Exchange organization and Exchange Online.

Enable Exchange Online users to send mail to a dynamic distribution list

You need to be assigned permissions before you can perform this procedure. To see what permissions you need, see the “Dynamic distribution groups” entry in the Mailbox Permissions topic.

Consider the scope of the dynamic distribution group before the hybrid deployment and before the mailboxes were moved to Exchange Online. If the scope included only mailboxes, the scope must be expanded to include mail users and mail contacts. To do this, follow these steps:

  1. On an on-premises Exchange server, start the Exchange Management Console (EMC).

  2. In the console tree, navigate to Recipient Configuration. Beneath that, navigate to Distribution Group.

  3. In the results pane, click the dynamic distribution group that you want to configure.

  4. In the Action pane, click Properties.

  5. On the Filter tab, select The following specific types, and then click to select the Users with Exchange mailboxes and the Users with external e-mail addresses check boxes.

  6. Click Apply. Then, click OK.

To create a contact in Exchange Online to represent the dynamic distribution group, follow these steps:

  1. Sign in to Outlook Web App on the Office 365 tenant by using a service administrator account.

  2. Click Options, and then click See all options.

  3. Click Manage Myself, and then click Manage Organization.

  4. Click Users and Groups, and then click External Contacts.

  5. Click New, and then type the contact details.

  6. In the External e-mail address box, type the mail address of the Dynamic Distribution group that was created on the on-premises Exchange server.

  7. Click Save.

Exchange Online users can now select the dynamic distribution group from the global address list (GAL). When they do, messages will be delivered to the members of the group as defined by the settings for the group.

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