"Delivery has failed" and "550 5.1.1 RESOLVER.ADR.RecipNotFound" NDR after a mailbox is moved to Office 365

Applies to: Exchange OnlineExchange Server 2013 EnterpriseExchange Server 2013 Standard Edition

Note The Hybrid Configuration wizard that's included in the Exchange Management Console in Exchange 2010 is no longer supported. Stop using the old Hybrid Configuration wizard and instead use the Office 365 Hybrid Configuration wizard at http://aka.ms/HybridWizard. For more information, see Office 365 Hybrid Configuration wizard for Exchange 2010.


Assume that you have a hybrid deployment of on-premises Microsoft Exchange Server and Exchange Online in Microsoft Office 365. You use the Mailbox Replication Service through the Exchange Management Console or the Exchange Management Shell to move a mailbox from the on-premises environment to Office 365. However, after the mailbox is moved, on-premises users and external users can't send mail to that mailbox in Office 365. The sender receives the following non-delivery report (NDR):
Delivery has failed to these recipients or groups:

<Recipient email address>

Your e-mail was not delivered to all intended recipients. The e-mail address you specified doesn't exist, or may have been recently deleted. Please also check to ensure you typed the address properly. It is possible that your contact's e-mail address has changed and Outlook's AutoComplete has the old address stored. If this is the case, start typing their name in the To line, press the down arrow to select the outdated entry, and then press Delete. Now use the address book to locate the correct e-mail address.

Diagnostic information for administrators:

Generating server: <>

<Recipient email address>

#< #5.1.1 smtp;550 5.1.1 RESOLVER.ADR.RecipNotFound; not found> #SMTP#


This issue may occur if the on-premises mail-enabled user who represents the moved mailbox isn't stamped correctly with the target address. The Exchange server generates an NDR message because the on-premises Active Directory Domain Services (AD DS) can't locate the user in order to route the mail correctly.


To resolve this issue, add the target address, also known as the service routing address, to the mail-enabled user in the on-premises environment. To do this, use one of the following methods.

Method 1: Use the Exchange Management Console

  1. Open the Exchange Management Console on your local Exchange 2010 server.
  2. Click Microsoft Exchange On-Premises, and then click Recipients Configuration.
  3. Right-click the user, and then click Properties.
  4. On the E-mail Addresses tab, click Add, click SMTP Address, and then enter the email address. Use the <alias>@<domain>.mail.onmicrosoft.com format for the email address.
  5. Select the name that you entered, and then click Set as Routing Address.
  6. Click OK.

Method 2: Use Exchange Admin Center

  1. In a web browser on your local Exchange 2013 server, browse to the Exchange Admin Center,
  2. Click Recipients, and then click Mailboxes.
  3. Click the user, and then click Edit.
  4. Click Email Address, and then click Add, .
  5. Under Email Address, click SMTP, and then enter the email address. Use the <alias>@<domain>.mail.onmicrosoft.com format for the email address.
  6. Click OK, and then click Save.

Method 3: Use Active Directory Service Interfaces Editor (ADSI Edit)

Warning This procedure requires ADSI Edit. Using ADSI Edit incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems that result from the incorrect use of ADSI Edit can be resolved. Use ADSI Edit at your own risk.
  1. Click Start, click Run, type adsiedit.msc, and then click OK.
  2. Locate and right-click the user, and then click Properties.

    Note To determine the container to which the user belongs, view the user properties in the Exchange Management Console.
  3. Click the Attribute Editor tab, and then double-click Target Address.
  4. Type the external Simple Mail Transfer Protocol (SMTP) address.
  5. Click OK.
After the service routing domain is set up, confirm that the issue is resolved.


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