Article ID: 2730609 - View products that this article applies to.

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PROBLEM

You have an Microsoft Exchange hybrid deployment in which cloud-based users in Microsoft Office 365 and on-premises users have the same email namespace (such as alias@contoso.com). However, on-premises users aren't getting email messages from Office 365 users.

Additionally, when an Office 365 user sends an email message to an on-premises user, the Office 365 user receives a nondelivery report (NDR) error message that resembles the following:
#550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ##

SOLUTION

This occurs if the domain that's set up in the hybrid deployment isn't set as a shared domain in Office 365. To fix this issue, set up the domain as a shared domain. To do this, follow these steps:

Use Exchange Admin Center if you have Office 365

  1. Sign in to the Office 365 portal (https://portal.microsoftonline.com) as a global admin.
  2. In the header, click Admin, and then click Exchange.
  3. In the left navigation pane of the Exchange Admin Center, click Mail Flow, and then click Accepted Domains.
  4. Select the domain that is set up for the hybrid deployment, and then click Details.
  5. Select Shared, and then click Save.

Use Exchange Control Panel if you have Office 365 pre-upgrade

  1. Sign in to the Office 365 portal (https://portal.microsoftonline.com) as a global admin or a service admin.
  2. Click Admin, and then under Exchange Online, click Manage.
  3. In Exchange Control Panel, click Mail Control, and then click Domains & Protection.
  4. Select the domain that is set up for the hybrid deployment, and then click Details.
  5. Select Shared, and then click Save.

MORE INFORMATION

The Exchange Admin Center and the Exchange Control Panel lists the domains that you added to your account through the Microsoft Office 365 portal. It lets you manage how messages are delivered. In a hybrid scenario, Exchange Online must be set up correctly so that when a cloud-based user sends an email message to an on-premises user, Exchange Online routes the email message to the on-premises messaging environment. 

For more info about accepted domains, go to the following Microsoft TechNet website:
Accepted domains

For more info about hybrid deployment, go to the following Microsoft TechNet website:
Exchange Server Deployment Assistant
Still need help? Go to the Office 365 Community website.

Properties

Article ID: 2730609 - Last Review: September 11, 2013 - Revision: 10.0
Applies to
  • Microsoft Office 365 for enterprises (pre-upgrade)
  • Microsoft Office 365 for small businesses  (pre-upgrade)
  • Microsoft Office 365 for education  (pre-upgrade)
  • Microsoft Exchange Online
Keywords: 
o365 hybrid o365062011 pre-upgrade o365022013 after upgrade o365a o365e o365p o365m KB2730609

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