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We're currently preparing for a Microsoft 365 tenant consolidation after our company acquired another business. The mailbox migration itself seems manageable, but we're more concerned about everything surrounding it—shared mailboxes, OneDrive ownership, SharePoint permissions, and ensuring employees can continue working without disruption.
One of our biggest worries is preserving permissions correctly. Several departments rely on shared mailboxes and collaborative SharePoint libraries every day, and rebuilding access manually after the migration would be extremely time-consuming. We're also trying to avoid duplicate content because both tenants contain similar files and historical email data.
While researching migration options, I found the DRS Softech Office 365 Tenant to Tenant Migration Tool. The documentation mentions incremental migration, flexible mailbox mapping, Modern Authentication, real-time monitoring, and reporting, which seem useful for projects involving multiple workloads instead of just Exchange Online.
We're planning a pilot migration first, followed by department-wise migrations over several weekends. However, I'm still unsure about the best way to validate permissions, mailbox access, SharePoint libraries, and OneDrive ownership before declaring the migration complete. Management also expects a detailed audit trail showing exactly what was migrated and whether anything failed.
Has anyone recently completed an O365 tenant to tenant migration involving mergers or acquisitions? How did you verify mailbox permissions, shared resources, and OneDrive ownership after migration? Did you experience any unexpected issues with Microsoft 365 groups, shared mailboxes, or permission inheritance? I'd appreciate hearing practical experiences before we finalize our migration schedule.
One of our biggest worries is preserving permissions correctly. Several departments rely on shared mailboxes and collaborative SharePoint libraries every day, and rebuilding access manually after the migration would be extremely time-consuming. We're also trying to avoid duplicate content because both tenants contain similar files and historical email data.
While researching migration options, I found the DRS Softech Office 365 Tenant to Tenant Migration Tool. The documentation mentions incremental migration, flexible mailbox mapping, Modern Authentication, real-time monitoring, and reporting, which seem useful for projects involving multiple workloads instead of just Exchange Online.
We're planning a pilot migration first, followed by department-wise migrations over several weekends. However, I'm still unsure about the best way to validate permissions, mailbox access, SharePoint libraries, and OneDrive ownership before declaring the migration complete. Management also expects a detailed audit trail showing exactly what was migrated and whether anything failed.
Has anyone recently completed an O365 tenant to tenant migration involving mergers or acquisitions? How did you verify mailbox permissions, shared resources, and OneDrive ownership after migration? Did you experience any unexpected issues with Microsoft 365 groups, shared mailboxes, or permission inheritance? I'd appreciate hearing practical experiences before we finalize our migration schedule.