This guide contains all the necessary steps for migrating email data from one Microsoft 365 instance to another Microsoft 365 instance using Graph API in both endpoints.

MigrationWiz

MigrationWiz is not a sync tool. Already migrated items updated at the source mid-migration will not be updated at the destination.

MigrationWiz supports the capability to share migration projects across a Workgroup. When the Project Sharing feature is turned on, all active agents can view all migration projects.

First Time?

If this is your first time performing a migration, we have created a Migration Planning & Strategy Guide to walk you through planning, set-up, and general migration best practices. If you have never performed a migration before, we suggest reading that before beginning the steps outlined in this scenario.

Prerequisites

It is important to highlight and meet the following prerequisites for a smooth migration project.

Licensing

Purchase and apply User Migration Bundle licenses for all the users being migrated. For this migration type, we suggest the User Migration Bundle. For other licensing options, like the Tenant Migration Bundle, please refer to Which Migration License Do I Need?.

• User Migration Bundle Licenses have unlimited data available per license.
• User Migration Bundle Licenses are applied to the customer's users and expire 12 months after their purchase date. 
• OneDrive projects are all included when using User Migration Bundle Licenses.
• This license type must be applied manually.

To use your license by following the next steps:

1. Review Considerations.
2. Purchase Licenses.
3. Create a Customer.
4. Apply Licenses.

Limitations

• We recommend completing this migration with multiple migration passes as instructed in the MigrationWiz steps, as this will cause the least impact on the users.
• Due to Microsoft limitations, using Delegate Permissions with Graph API is not supported at this time. Only Application Permissions can be used.
• Pinned/Flagged Emails are migrated but not Pinned/Flagged in the destination environment.
• The following Rule actions are unsupported by Graph API:
  • Server Reply
  • SMS Alert
  • Play Sound
  • Run Script
  • New Item Alert
  • Flag Message
  • Pin to Top
• Threading (email messages that belong to the same conversation) is not supported and will require Manual implementation. 
• Delegate-level calendar access isn't supported by Microsoft Graph. It's automatically downgraded to Free/Busy-only.
• Archive Mailbox as a destination is currently not supported. Support for this option is planned for a future release.

Migrated Items

Please click the bars below to check the migrated and non-migrated items. We are constantly working to create a better migration experience for you so these items may change over time.

Prepare the Source Environment

Modern Authentication Requirements

The KBs listed in the Exchange Online Authentication options using Graph API section will help you configure both the source and destination tenants when using Microsoft 365 with the Microsoft Graph API. A Global Administrator account is required to consent to the BT app or create and consent to the BYO app, since the Entra app's permission types require global admin approval.

Export the User List to a CSV File

This can be used when bulk-adding users to your MigrationWiz project later. You can copy and paste the user list into the Source and Destination Email columns within your MigrationWiz project dashboard under Add > Bulk Add.

To export the user list:

1. Go to the Microsoft 365 admin portal.
2. Click Users.
3. Click Active Users.
4. Click Export.
5. Click Continue.

Be sure to save the CSV somewhere you can access it for upload later in the migration.

Prepare the Destination Environment 

Modern Authentication Requirements

The KBs listed in the Exchange Online Authentication options using Graph API section will help you configure both the source and destination tenants when using Microsoft 365 with the Microsoft Graph API. A Global Administrator account is required to consent to the BT app or create and consent to the BYO app, since the Entra app's permission types require global admin approval.

Set Up User Accounts

Set up user accounts on the destination Office 365 tenant and assign licenses. These can be created in several ways. (The following links are to external articles.)

• Manually, one at a time.
• By bulk import, via CSV file. 
• By PowerShell script. 

MigrationWiz Steps

Create a Mailbox Migration project

1. Click the Go to My Projects button.
2. Click the Create Project button.

3. Create a Mailbox project.

   Important

   For mailbox migrations, use the migration service account credentials to access mailboxes. In most migration scenarios, this account must have full access rights to the Source mailboxes.

4. Click Next Step.
5. Enter a Project name and select a Customer.
6. Click Next Step.
7. Select endpoints or follow the steps below to create new ones.
8. Click Save Project.

Endpoints

Endpoints are created through MigrationWiz. If you select an existing endpoint from the dropdown, it will only show ten endpoints. If you have more than ten, you may need to search it.

Consider that endpoint search is case and character-specific. For example, Cust0mer will not show up if the search is customer. We recommend keeping a list of endpoints you have created, along with any unique spellings or capitalization you may have used.

Create your Endpoints

Please review the following tabs to create your destination and source endpoints.

Add Users

Add the user accounts that will be migrated to the project. This may be done in several ways, depending on the size of the project. Steps for each option are in the accordion below, simply click to show the option you select and follow the guidance there.

Small Migrations

For small migrations, it is easy to add users one at a time using Quick Add. You can find the steps for this type of migration, below.

Larger Migrations

For larger migrations, we recommend either using the Autodiscover or Bulk Add option.

Advanced Options

Support Tab

• InitializationTimeout=8 This increases the initialization timeout window to eight hours. This value is in hours, up to a maximum of 100 hours. Values above 100 are in milliseconds. For example:​
  • InitializationTimeout=2 will increase the timeout to 2 hours.
  • InitializationTimeout=8 will increase the timeout to 8 hours.
  • InitializationTimeout=14400000 will increase the timeout to 4 hours.
  • InitializationTimeout=21600000 will increase the timeout to 6 hours.
     
• Using the (RecipientMapping=) support option in your project. 

Bulk Load

To upload a large list of Advanced Support options, see the Bulk Load - Advanced Options when Migrating Mailbox projects using Graph API for additional guidance.

Run Verify Credentials

You may verify the credentials of items in MigrationWiz without migrating data or consuming any licenses.

1. Open the Project containing items you wish to validate.
2. Select the items you wish to validate.
3. Click the Start button in your dashboard.
4. Select Verify Credentials from the drop-down list.

Once complete, the results of the verification will be shown in the Status section.​ 

Run a Pre-Stage migration pass

1. Select the users.
2. Click the Start button from the top.
3. Select Pre-Stage Migration.
4. Uncheck the box named Automatic Replies (This option will be removed from the Pre-Stage pass at a later date)
5. Under the Migration Scheduling section, from the drop-down list, select 90 days ago.
6. Click Start Migration.

The 90 days is a suggestion, you can select any option you prefer. The Pre-Stage migration will migrate only older mail items. This can be run multiple times with different timeframes selected to migrate data in smaller chunks.

Remove Domain from Source

This should only be done after the Pre-Stage migration pass has been completed. Typically, it is done late on a Friday night. If you need instructions for removing a domain, refer to this document from Microsoft: Remove a domain from Office 365.

If there are several domains in the Source tenant being moved to the new tenant, all of them need to be removed.

In the admin portal, change the UPN of the migration service account to the onmicrosoft.com address.

After domain removal, users will not be able to access their email, unless they know and log in with their tenantname.onmicrosoft.com email addresses.

After removal, wait 30 minutes for domain removal replication to complete.

Verify Domain at Destination

These actions are performed from within the Tenant 2 (Destination) admin portal.

1. Verify the domain in the Destination Microsoft 365 account. We recommend the use of the wizard in Microsoft 365 for this since once the domain is verified with the Text record, it offers to change all the users to the new Default Domain. Since the domain was previously added to the account, all that needs to be done is to click the Verify button. If the domain is unable to be verified, and there is an error saying the domain already exists on another account, contact Microsoft Support at 1-800-642-7676 (US Toll-Free, other numbers are also available), and tell them that the domain needs to be manually de-provisioned from Forefront, also known as Exchange Online Protection or EOP.
2. Confirm that every user has the Destinationdomain.com domain name added to their mailbox.
3.  Download the add_new_domain.ps1 PowerShell script to check for this and add the domain name. This is only necessary if the users do not have the new default domain added to their account.

MX Record Cutover

On the DNS provider's portal, change the primary MX record to reflect the DNS settings for the new Microsoft 365 organization. DNS settings to change include Autodiscover, MX, and SPF records. Also, remove the old settings for Tenant 1. These settings can be found in the Microsoft 365 admin portal, by following these steps:

1. Inside Microsoft 365, click Admin in the header.
2. On the Admin page, click Domains in the left pane.
3. Click the domain name to be set up, and then click the DNS Settings This page lists the DNS records necessary to use the Microsoft 365 services.

Full (Delta) pass

1. Select the users.
2. Click the Start button from the top.

3. Select Full Migration.

   Important

   It is recommended to only migrate Automatic Replies in the last migration pass for the user.

4. Click Start Migration. This migration will be completed quickly since most data is migrated during the Pre-Stage migration; Microsoft 365 to Microsoft 365 migrations have high bandwidth available.
5. Look through the user list and click any red "failed migration" errors. Review the information and act accordingly.

Run Retry Errors

Each error logged represents an item that was not migrated. MigrationWiz contains a mode in which you can resubmit the migration to retry failed items. This mode of operation is always free of charge. You may only submit mailboxes in this mode only if they satisfy all of the following conditions:

1. The last migration was completed successfully.
2. The mailbox contains at least one error.

If your mailbox does not satisfy these conditions, you will receive a warning when submitting the migration in this mode and your request will not be fulfilled.

To submit one or more mailboxes in retry mode, perform the following steps:

1. Click the Go To My Projects button.
2. Select the project that contains the mailboxes that you want to retry.
3. Select the mailboxes that have migration errors.
4. Click on the Start button.
5. Select Retry Errors from the menu.
6. Click the Retry Errors button.

When errors are repaired, they will disappear from the error log. Some errors may not disappear if the Source item was not reprocessed (due to filters, for example), was not deleted or moved, or if the item failed again. 

If problems persist, contact Support. 

Final Steps

Users must create new Outlook profiles, set up their signatures again, and reattach any PST files attached to their previous profile.

Click the bar chart icon in the MigrationWiz dashboard to receive an email containing all the project migration statistics. 

Related Topics

• Authentication Options using Graph API
• Exchange Online Advanced Options using Graph API