Error: Cannot find a recipient that has mailbox GUID in Cross-Forest Migration

Symptoms:

Error when moving mailbox: Cannot find a recipient that has mailbox GUID.

The following snapshot shows the result of running New-MoveRequest:

 

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The error is: Cannot find a recipient that has mailbox GUID

Problem:

The error is clearly saying that there is no Mail Enabled User (MEU) with the mandatory attribute msexchmailboxguid, however when we check the MEU LDAP property:

 

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The problem here that when the remote forest implies a child name relationship, Exchange 2010 will think that this is a child domain and then the strange error will be returned. In our case the source forest name is egypt.tailspin.com and the target forest name is tailspin.com so Exchange will think that the target is child domain from the source forest and it will fail.

The following KB2598985 (which just released from 3 days) is talking about this scenario. https://support.microsoft.com/kb/2598985

Solution:

Before the release of Exchange 2010 SP2 Rollup Update 1 the solution one of the following painful options:

  1. Export all mailboxes as PST files from the source forest and then import it in the target forest: this option is based on big bang approach where there is no co-existence. This option might be considered in small companies where we can disconnect the source forest, export the PSTs and import it to the target forest in reasonable downtime.
  2. Co-Existence: when co-existence is required in enterprise companies with thousands of users the only option will be creating Intermediate Forest: Create new forest with different name (ex: intermediate.local), move mailboxes from source forest to the intermediate forest, then move the mailboxes again from the intermediate forest to the target forest, this option explained in details in my earlier blog post: Exchange 2010 Cross-Forest Migration Step by Step Guide – Part III (https://blogs.technet.com/b/meamcs/archive/2011/10/25/exchange-2010-cross-forest-migration-step-by-step-guide-part-iii.aspx)

 

Note: This problem has been solved with Exchange 2010 SP2 RU1 which you can get from the following URL: https://www.microsoft.com/download/en/details.aspx?id=28809 .