Using Outlook for tenant to tenant migration of Office 365 mailboxes via PST export import
Acquisitions and mergers between organizations are always followed by the consolidation of their assets—on-premises as well as cloud. In most cases, Office 365 mailboxes need to be migrated from one tenant to another. This article will show you how you can use the desktop version of Outlook to achieve this migration.
Migrate Office 365 mailboxes from one tenant to another
An Outlook Data File (PST) can carry mailboxes from one Office 365 tenant to another. This migration is accomplished in three steps:
Exporting Office 365 mailbox to Outlook PST using the eDiscovery PST Export Tool
Use the eDisocovery Tool, a feature associated with the compliance management (in Exchange admin center), to export a mailbox or selected items to PST format and to make them accessible in MS Outlook. The account performing the PST conversion should have Mailbox Import Export role assigned to it. After creating a mailbox search in in-place eDiscovery & Hold, the entire mailbox or its items can be exported to PST using the eDiscovery PST Export Tool.
Adding the second tenant’s Office 365 account to Outlook
The desktop version of Outlook acts as an intermediator between two Office 365 tenants. Adding the second tenant’s Office 365 email id to Outlook makes their folders and items available in Outlook and vice versa (due to synchronization). In Outlook itself, you can create a new empty folder within the folder hierarchy of Office 365 in order to import the PST file.
Importing the PST file to Outlook
The desktop version of Outlook can import a PST file directly to an Office 365 account that is added to it. Folders and items imported to Outlook will automatically will be available in the Office 365 account as both accounts get synchronized. The PST file (created by exporting the mailbox of the first tenant) can now be imported to Outlook (more specifically, to the destination folder created in the second tenant’s Office 365 folders). After this is complete, you are able to access the first tenant’s Office 365 account through the second tenant’s one.
Migrating Office 365 mailboxes from one tenant to another using Outlook on the desktop is a simple process. However, it starts becoming ineffective when you have to deal with a large number of mailboxes. When this occurs, many IT teams choose to simplify the migration with the help of automated solutions like LepideMigrator for Exchange or this import/export tool.