Anyone Recently Migrate Shared Mailboxes between Office 365 Tenants?
Our organization is preparing for a Microsoft 365 tenant consolidation due to Mergers & Acquisitions, and we're currently evaluating the safest way to Migrate Shared Mailboxes between Office 365 Tenants. User mailboxes seem relatively straightforward, but shared mailboxes are a different story because multiple teams rely on them every day.
These shared mailboxes contain years of customer communication, internal discussions, and departmental records. They're also configured with delegated permissions for several users, so preserving mailbox access and folder hierarchy is a major priority. We also want to avoid duplicate emails if the migration has to be completed in multiple phases.
Initially, we planned to use Microsoft's native migration process, but after reviewing the documentation, it seems like there will be a significant amount of PowerShell scripting, mailbox mapping, permission management, and post-migration validation. Since our environment is fairly large, we're exploring alternatives that could simplify the process.
I've been researching different DRS Softech Office 365 Tenant to Tenant Migration Tool solutions that can automate mailbox mapping, support incremental migration, and generate detailed migration reports. During my search, I came across the DRS Softech Office 365 Tenant to Tenant Migration Tool. It appears to support Exchange Online, SharePoint Online, OneDrive, Modern Authentication, and Microsoft Graph API, which seems suitable for enterprise migration projects.
At this stage, we're simply comparing different migration approaches before making a final decision. If anyone has handled a similar migration recently, I'd be interested in learning which workflow or migration strategy proved to be the most efficient for moving shared mailboxes between Microsoft 365 tenants.
Comments
Yes, I recently moved some shared mailboxes from one Microsoft 365 tenant to another. The mailbox data was transferred quite seamlessly, but what is more important is that it was the planning of the migration that was vital before starting the data move process. What I did at first was recreate the mailboxes in the target tenant and give the necessary permissions, and then test them with several users before moving the rest of the mailboxes.
When you are dealing with a small migration, the standard Microsoft options might do the job. However, since we had several mailboxes to migrate, I decided to use Softaken Office 365 to Office 365 Migration Software because it simplified the mailbox transfer without requiring manual export and import steps.
What I found useful in this tool:
* Supports shared and user mailbox migration.
* Preserves emails, attachments, folder hierarchy, and metadata.
* Handles multiple mailboxes in one process.
* Allows selective migration with filters.
* Reduces manual effort during tenant consolidation.
One recommendation: don't remove the old tenant immediately. Let users verify that shared mailbox access and permissions are working correctly before completing the migration.