Forum Discussion
Tenant to tenant migration error
I am performing a tenant to tenant migration and have done all of the steps up to creating a migration batch. I am migrating one 365 tenant to another 365 tenant. I am migrating 2 users and both have the below error in the batch.
Error: CommunicationErrorTransientException: The call to 'https://mw4pr07mb8700.namprd07.prod.outlook.com:64350/mrs/Microsoft.Exchange.MailboxReplicationService.ProxyService/OAuth' failed. Error details: Access is denied.. --> Access is denied.
Any assistance would be greatly appreciated.
2 Replies
- Are you using the mrs proxy from microsoft for the migration?
Hi Ben_H3,
you are encountering a "CommunicationErrorTransientException" with the error message "The call to 'https://mw4pr07mb8700.namprd07.prod.outlook.com:64350/mrs/Microsoft.Exchange.MailboxReplicationServi...' failed."
That could be the issue with Admin consent to the application in the source tenant.
Make sure you used correct tenant domain in the consent URL.
Also, make sure your OAuth Application ID is associated to the Migration Endpoint.
Cross-tenant mailbox migration - Microsoft 365 Enterprise | Microsoft Learn
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Kindest regards
Leon Pavesic
