Migrating mailboxes from Exchange Server to Exchange Online for a single target

Migrating mailboxes from Exchange Server 2013 or 2016 to Exchange Online is supported through the use of a single mixed target.
To migrate mailboxes from Exchange Server to Exchange Online:
  1. Ensure that the Use Autodiscover Service option is enabled. To enable the option:
    1. In NexJ Admin Console, navigate to the Synchronization page.
    2. In the Synchronization tab, in the Targets list, select the appropriate Exchange server target.
      Details for the server display in the right side of the page.
    3. Click the Edit button on the top right of the page and in the dialog, select Use Autodiscover Service.
  2. In NexJ Admin Console, navigate to the Synchronization page and ensure that streaming is specified as the subscription type on the Exchange server target:
    1. Select the Exchange target server.
    2. In the Exchange Server EWS zone, click the Edit button on the top right of the page.
      The Edit Exchange Server dialog opens.
    3. In the Subscription Type field, select Streaming.
    4. Click OK.
      The Edit Exchange Server dialog closes. Note that subscriptions to user folders do not occur immediately.
  3. Using Exchange Server, migrate the mailboxes that you want to move from Exchange Server to Exchange Online.
  4. In NexJ Admin Console, navigate to the Synchronization page and run the Autodiscover batch job:
    1. Select the Exchange target server.
    2. Click Configure in the Global Options field in the pane on the right side of the page.
      The Global Exchange Synchronization Options dialog opens.
    3. Click the Auto Discover tab.
    4. Click the Run Auto Discover Now button to run autodiscover.
      Autodiscover runs and the version for the migrated users changes to 2013 or 2016. Note that inbound streaming does not occur immediately and should occur within 30 minutes.
You have migrated mailboxes from Exchange Server to Exchange Online using a single target.