Staged migration mail sync error

Question

Hello

We have some problems migrating mail to Office 365. Endpoint creating went ok, and Azure AD connect en syncing users also works OK

But when i create an csv batch, after some time this error occurs and synchronisation stopped.

Data migrated:  

Migration rate:  

Error: MigrationTransientException: Failed to update the on-premises mailbox with the target address ‎(SMTP:******@somedomain.onmicrosoft.com)‎. The mail sent to the user will not reach user‎'s hosted mailbox. The error might be due to account credentials used for migration not having enough permission to write data back into the on-premise AD. Please ensure that the account credential has Domain Admin privilege. --> We weren‎'t able to connect to the remote server. Please verify that the migration endpoint settings are correct and your certificate is valid, and then try again. Consider using the Exchange Remote Connectivity Analyzer ‎(https://testexchangeconnectivity.com)‎ to diagnose the connectivity issues.

Answer 1

Hi FrisoTrip,

Thanks for your update. 

As the article suggests that Exchange 2010 is not supported with Staged Migration, that is the thing which needs to consider. On another hand, since you created a ticket with Microsoft on Thursday, may I know the ticket numner (Service Request number) so that we can help monitor the whole process of the ticket. 

For protecting your privacy, you can provide it in the PM. 

Regards,

Alan

Answer 2

Hi FrisoTrip,

If you have any update about this case, please let me know. I will further assist you if it is necessary. 

Regards,

Alan

Alan

I am not at work at the moment. I can tell you that our client is running exchange 2010. I know it is not supported when i do an staged migration, but we did it with other clients an that worked OK.

Also i have created an ticket with microsoft on thursday, but we haven"t had contact by telephone.

So i will try it on monday and hopefully the have an solution to this strange problem.

What we want is migrate mailboxes to office 365 and decommision the old exchange server, but keep password sync in place.

We have done this with two scenario's: cutover and after that install azure ad connect and at last convert mailuser to mailenabled users. That worked ok

Also we did the sam for staged migrations.

Friso

Answer 3

Hi FrisoTrip,

If you have any update about this case, please let me know. I will further assist you if it is necessary. 

Regards,

Alan

Answer 4

Hi FrisoTrip,

Firstly, I'd like to lsit some pre-requisites of Staged Migration (if you know it, let's move forward to the followings). For example, the Exchange on-premises version should be Exchange 2003 or Exchange 2007. The latter version of Exchange on-premises like Exchange 2010, Exchange 2013 is not supported for Staged Migration. And, it needs to verify the custom domain used in on-premises in Office 365 before migration. For more information, you can refer to https://support.office.com/en-us/article/what-you-need-to-know-about-a-staged-email-migration-to-office-365-7e2c82be-5f3d-4e36-bc6b-e5b4d411e207. 

If all is OK, let's focus on the migration errors of "Failed to update the on-premises mailbox with the target address" and "The error might be due to account credentials used for migration not having enough permission to write data back into the on-premise AD". 

1. "Failed to update the on-premises mailbox with the target address". For it, please make sure you have verified the on-premises custom domain in Office 365 and each of the synchronized account in Office 365 is using the verified domain (on-premises domain). If you find any account doesn't meed the condition, you can try SMTP match and re-perform the migration again. https://support.microsoft.com/en-sg/help/2641663/how-to-use-smtp-matching-to-match-on-premises-user-accounts-to-office
2. "The error might be due to account credentials used for migration not having enough permission to write data back into the on-premise AD“. For it, make sure you are conducting the migration with the global admin. If possible, you can try with another admin's credential to migrate again. 

If the issue persists, I'd like to collect the following information for moving forward:

1. the Exchange Remote Connectivity Analyzer test for the connection (Outlook connectivity). 
2. The complete migration error report(s).
3. A creenshot about the error message. 

In consideration of the privacy, I suggest you provide the above mentioned information in the Private Message (PM). 

Regards,

Alan