Microsoft Purview in the Real World (Dec 16, 2022)
Published Dec 16 2022 03:10 PM 1,439 Views





















This document is not meant to replace any official documentation, including those found at  Those documents are continually updated and maintained by Microsoft Corporation.  If there is a discrepancy between this document and what you find in the Compliance User Interface (UI) or inside of a reference in, you should always defer to that official documentation and contact your Microsoft Account team as needed.  Links to the data will be referenced both in the document steps as well as in the appendix.

All the following steps should be done with test data, and where possible, testing should be performed in a test environment.  Testing should never be performed against production data.


Target Audience

Presales Technical Specialist running Endpoint DLP testing


Document Scope

The purpose of this document (and series) is to provide insights into various user cases, announcements, customer driven questions, etc.



Topics for this blog entry

Here are the topics covered in this issue of the blog:

  • Migrating large mailboxes to a new tenant that ALSO happen to be on legal hold.




This blog series and entry is only meant to provide information, but for your specific use cases or needs, it is recommended that you contact your Microsoft Account Team to find other possible solutions to your needs.




Migrating large Exchange Online Mailboxes (on Legal Hold) to a new Tenant

If you are an organization how is moving email data from one tenant to another, the following questions might arise:


Question #1 – What are possible sticking points for migrating large Exchange Online Mailboxes that have data that is on legal hold?


Answer #1 – The link below will connect you to the primary Microsoft document that addresses this is covered in.  Most, if not all, documents you find will refer back to this document.


Cross-tenant mailbox migration - Microsoft 365 Enterprise | Microsoft Learn (root page)


Question #2 – What if the mailbox being migrated is in an Auto Expanding Archive?  Can that data be migrated?

Answer #2 – Yes, this data can be migrated, but you will need to have the ArchiveGUID  in both the source and target tenants.






Question #3 – What the known issues with migrating mailboxes that are auto expanded?

Answer #3 – See the information below from the official documentation.


Cross-tenant mailbox migration - Microsoft 365 Enterprise | Microsoft Learn (Known Issues)





Question #4 – Does Microsoft have services that can help with migrating large mailboxes with legal hold data.

Answer #4 – Microsoft does provide several post-sales options to help with mailbox migrations.  I recommend you reach out to your Microsoft account team to understand these options.  There are also Microsoft partners that can help with this issue.  You can research them yourself or contact your Microsoft account team for their recommendations.


Appendix and Links

What happens to Litigation Hold data of Litigation Hold is turned off? - Microsoft Community Hub

Create a Litigation hold - Microsoft Purview (compliance) | Microsoft Learn

Learn about auto-expanding archiving - Microsoft Purview (compliance) | Microsoft Learn

Cross-tenant mailbox migration - Microsoft 365 Enterprise | Microsoft Learn (root page)



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‎Aug 11 2023 05:14 PM
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