Simplified Guide to Office 365 Tenant to Tenant Migration

Moving data from one Office 365 tenant to another may feel like a heavy task, but it's something many businesses need to do during mergers, acquisitions, or reorganizations. This process, called Office 365 tenant to tenant migration, involves transferring mailboxes, OneDrive files, and sometimes other data like SharePoint or Teams to a new tenant. In this article, we'll explain what this migration is, how it works, and why the manual method has some limits. Let's break it down in a way that's easy to understand!

What is Office 365 Tenant to Tenant Migration?

An Office 365 tenant is like a digital home for your organization's data—think emails, files, and collaboration tools like Teams. When a company needs to move this data to a new tenant, it's called Office 365 tenant to tenant migration. This usually happens when two businesses merge, one company buys another, or a business wants to reorganize its digital setup.

The goal is to move data smoothly without losing anything or disrupting work. The main parts of this migration often include:

• Mailboxes: Emails, calendars, and contacts.
• OneDrive: Files and folders stored in the cloud.
• Other services: SharePoint sites or Teams data (though these often need extra tools).

Manual Office 365 Mailbox Migration: What You Need to Know

One way to do Office 365 tenant to tenant migration is the manual method, which uses Microsoft's built-in tools like PowerShell scripts. This method is free (except for licensing costs) but requires technical know-how and careful planning. Here's how it works and what it covers:

What the Manual Method Supports

The manual method mainly supports:

• Mailbox Migration: You can move emails, calendars, and contacts from one tenant to another. This is called manual Office 365 mailbox migration.
• Cross-Tenant OneDrive Migration: You can also transfer OneDrive files and folders using tools like SharePoint Online PowerShell.

However, the manual method has limits. It only supports mailboxes and OneDrive migrations. If you want to move SharePoint sites, Microsoft Teams data, or other services, you'll need third-party tools or professional help.

Licensing Requirements

To use the manual method, you need a Cross Tenant User Data Migration license. This is a one-time fee per user, and you can assign it to either the source (old tenant) or target (new tenant) user. This license is required for both mailbox and OneDrive migration, and Microsoft doesn't make exceptions. Without it, the migration will fail. You can buy this add-on for plans like Microsoft 365 Business Basic, Standard, Premium, or Enterprise plans (E3/E5).

Steps for Manual Migration

Here's a quick overview of the manual process:

1. Prepare Both Tenants: Set up admin accounts, verify domains, and create user accounts in the target tenant.
2. Buy Licenses: Ensure you have the Cross Tenant User Data Migration license and enough Exchange Online licenses for the target tenant.
3. Set Up Permissions: Use PowerShell to establish a trust relationship between tenants.
4. Migrate Mailboxes: Use Exchange Online PowerShell to move mailboxes. Make sure the ExchangeGUID is set correctly to avoid errors.
5. Migrate OneDrive: Use SharePoint Online PowerShell to transfer OneDrive files. Ensure the source OneDrive is set to read/write, not read-only.
6. Test and Finalize: Check that emails and files work in the new tenant, then update mail routing (MX records) to point to the new tenant.

This process can take time and requires careful attention to avoid mistakes like data loss or downtime.

Limits of the Manual Method

While the manual method is cost-effective, it's not perfect. Here are some challenges:

• Limited Scope: It only handles mailboxes and OneDrive. For Teams, SharePoint, or other data, you'll need extra tools.
• Technical Skills Needed: You need to know PowerShell and Microsoft 365 admin tools.
• Time-Consuming: Manual migrations can take days or weeks, especially for large organizations.
• Risk of Errors: Mistakes in setup, like missing the ExchangeGUID, can cause migration failures or create duplicate mailboxes.

For businesses with more than 500 users or complex data, Microsoft recommends using a third-party tool or service provider to make the process smoother.

Why Consider Third-Party Tools?

Third-party tools like CloudBik offers, can migrate more than just mailboxes and OneDrive. They can handle Teams, SharePoint, and other services, often with less manual work. These tools offer:

• Automation: They simplify setup and reduce errors.
• Speed: They can migrate data faster, especially for large organizations.
• Reporting: You get detailed reports to track progress.
• Support: Many tools come with expert help if you run into issues.

However, these tools cost extra, so you’ll need to weigh the benefits against your budget. Also you can get custom solutions like OneDrive to OneDrive migration, if you are looking to migrate only OneDrive data.

Tips for a Smooth Migration

To make your Office 365 tenant to tenant migration successful:

• Plan Ahead: Map out what data you’re moving and test the process with a small group first.
• Communicate: Let users know what’s happening and train them on the new tenant.
• Check Licenses: Double-check that you have the Cross Tenant User Data Migration license and enough target tenant licenses.
• Backup Data: Save a copy of your data before starting, just in case.
• Test Everything: After migration, check that emails, files, and services work as expected.

Conclusion

Office 365 tenant to tenant migration is a big step, but with the right plan, it can go smoothly. The manual method is a good option for small businesses moving mailboxes and OneDrive, but it requires a Cross Tenant User Data Migration license and only covers those two areas. For larger or more complex migrations, third-party tools can save time and effort. By preparing well and following best practices, you can move your data to a new tenant without stress and keep your business running smoothly.