Google Groups to M365 Shared Mailbox Migration Guide

This article will guide you through migrating from Google Groups to Microsoft 365 Shared Mailbox.

You can easily set up a mailbox project and leverage the MigrationWiz solution to migrate your members, conversations, and attachments from Google Groups to your desired Microsoft 365 Shared Mailbox.


MigrationWiz is a migration tool, not a syncing tool. If changes are made at the source after migration, they will not sync to the destination, nor will changes made at the destination sync to the source. We do not have “live” monitoring of changes (as with a sync agent) and we cannot handle scenarios such as conflict resolution without user interaction.


It is important to note the following prerequisites to have a smooth migration project.

  • The source administrator must have a valid Google Vault license before proceeding with the migration project.
  • Google Groups requires “Conversation History” to be enabled for conversations to be kept. A collaborative inbox has “Conversation History” enabled by default. However, it is recommended to verify this in the Group’s setting.


The following are some of the limitations for the migration of Google Groups to Microsoft 365 Shared Mailboxes. Some of the limitations are an inheritance from the APIs used as well as the capabilities of the current destination.

  • External members from the source are not migrated as Microsoft Shared Mailboxes do not support external members.
  • Group settings (posting policy, member moderation, member privacy) are not migrated as Shared Mailbox instances do not support these settings.
  • A nested Group which is a member of other Groups will not be migrated.
  • Conversation tags like “Star”, “Abuse”, “Report”, and “Locked” are not migrated due to a lack of data from the source extract. The conversations are migrated.
  • Collaborative inbox features like “Assign to me”, “Assign to someone”, “Mark as completed”, “Mark as duplicated”, and “Mark as no actions” are not migrated as these are not supported in Microsoft Shared Mailboxes. The conversations are migrated.
  • Conversations under “Moderated” or “Pending” are not migrated due to a lack of data from the source extract.
  • In MigrationWiz, Google Groups messages are exported and migrated individually to the Shared Mailbox destination, while the Google Groups app shows the number of threads and messages within the thread. Therefore, there would be a mismatch of migrated item counts between what is indicated in MigrationWiz and Google Groups itself.
  • In MigrationWiz, Google Groups messages are exported and migrated individually to the Shared Mailbox destination, therefore, messages are shown as individual emails instead of their original conversation thread format. Prevent this issue by performing one of these two options:
    • Set the “Advance Option>Performance>Maximum number of concurrent migrations” to 3.
    • Create multiple projects to accommodate all the line items.


      MigrationWiz leverages PowerShell to migrate the project line items, hence, there is an inherited PowerShell concurrency limitation of 3 line items per run. Selecting more than 3 line items may result in a timeout error.
  • For now, UseMultiAdmin=1 is not working due to the Modern Authentication for Client ID and Tenant ID validates only a single Admin Username and password before saving the project for Google Groups to Microsoft 365 Shared Mailbox.

Which Items Are and Are Not Migrated

Which items are migrated?

Google Groups Members

  • Google Groups members' roles and permission (Owner, Manager, and Member) are mapped as “Full Access” in Microsoft Shared Mailbox

Google Groups conversation

  • Conversation metadata.
  • Conversation attachments.
  • Conversation labels.
Which items are not migrated?
  • Google Groups settings (Posting policy, members moderation, member privacy).

  • Collaboration Inbox features like ‘assignment of task’ and ‘status of tasks’.

  • Google Spaces.
  • Google Spaces Chats.
  • Conversation tags like “Star”, “Abuse”, “Report”, and “Locked”.
  • Conversations marked under “Moderated” or “Pending”.

  • External members.

  • Any nested Group which is a member of another Group.

Prepare the Source Environment

Google Groups Endpoint


This endpoint requires your tenant service account to be set up and Google APIs to be enabled. 


  • Subscription to Google Cloud Platform

  • Google Super Administrator account

  • Ability to set up a service account on the G Suite tenant

  • A service account must be set up before the MigrationWiz project is created

  • The administrator must have Google Vault access privilege

Create a Google Project

  1. Go to the Google Cloud Platform (GCP) Console and sign in as a super administrator. Choose one of the options below:

    • If you haven't used the Google Cloud Platform Console before, agree to the Terms of Service and click Create Project.

    • If you have used Google Cloud Platform Console before, at the top of the screen next to your most recent project name, click Down to open your projects list. Then, click New Project.

  2. Enter a project name and click Create.

Enable APIs for Service Account

  1. Click Menu () > APIs & Services > Library from the Google Cloud Platform Console,.

  2. Enable the following APIs by selecting the specific API and clicking Enable. Repeat for each API.

    • Groups settings API

    • Google Vault API

    • Admin SDK

Make sure that the respective services are enabled within the Google tenant. You can control services for your users by following the instructions on this page: G Suite and Google Services Access.

Create a Customer Tenant Service Account

  1. Click Menu > IAM & Admin > Service accounts from the Google Cloud Platform Console.

  2. Click Create Service Account and enter a name.

  3. Click Create.

  4. Assign the role of Owner to the new Service Account by selecting Owner from the Role drop-down menu.

  5. Click Done.

  6. You will now be returned to the Service Accounts page. 

  7. On the Service Accounts page, click the vertical ellipsis under the Actions column for the service account created above, and click on Manage Keys.

  8. Click + Add Key.

  9. Click Create New Key.

  10. Make sure that JSON is selected as the Key Type.

  11. Click Create.

  12. Click Close.

    • Make sure that you download the key as a JSON file and make a note of the name and location of the file. This JSON file will be used when setting up the migration endpoint in the mailbox migration project.

    • The JSON file must contain information in the following fields: “type”, “private key”, and “client email”. If these mandatory fields are empty, the file upload during endpoint creation will fail.

  13. From the service account that was set up in Step 3 (Create Customer Tenant Account):

    • Find the Unique ID field for that service account by clicking the Column Display Options “|||” button in the upper right corner above Actions.

    • Select the Unique ID checkbox.

    • Click Ok.

    • Copy the unique ID number. This is the Client ID number that will be used in a later step.

      • This Client ID should be considered similar to Administrator account passwords and handled securely.

Setting the Scopes for the Migration

From the Google Admin Dashboard:


  1. Click on Security.

  2. Click on API Controls.

  3. On the API Controls page, locate the section Domain-wide delegation.

  4. Click on Manage domain-wide delegation.

  5. Click on Add new.

  6. In the client Name field, enter the Service account's Unique ID.

  7. For OAuth scopes, enter the scopes listed below:

  8. Click Authorize.

Assigning Google Vault privileges

  1. The user must be a Super Administrator user and signed in as one.

  2. Sign in to Google Admin Console.

  3. In the Overview page, click on Admin Roles.

  4. Click on Create a New Role.

  5. Enter the Name and Description for the role, and click Continue.

  6. Find and expand the list on Google Vault, select the following:

    • Manage Matters.

    • Manage Searches.

    • Manage Exports.

    • View All Matters.

  7. Click Continue.

Prepare Destination Environment

Microsoft 365 Endpoint


  1. Set up user accounts on the destination Office 365 tenant and assign licenses. These can be created in several ways:

  2. Create an administrator account in Office 365 to be used for migration or use the global admin account for the tenant. The minimal service account requirements are either full access rights to the mailbox or impersonation rights. We recommend using impersonation over delegation because it is Exchange Online. For specific steps to set impersonation manually, see Impersonation and Delegation.

  3. Test that the administrator can access user mailboxes.
    Test access to the addresses, not to the addresses. Make sure that the account is attached to each mailbox in Office 365. By default, it should be attached, but if not, it will need to be added as an alias to each account. This can be done through the Office 365 admin portal or via PowerShell scripts. Read the Verify mailbox accessibility using EWS article for more information.

Modern Authentication Requirements

The steps listed in the Obtain Client and Tenant ID Settings for Mailbox and Exchange Online Migrations section of the Authentication Methods Migrations KB apply to both the source and destination tenant when they are Exchange Online, in regards to Exchange Web Services (EWS) in mailbox, archive mailbox, and public folder projects. Use a Global Administrator for the configuration steps.

Please review the documentation before preparing the destination.

MigrationWiz Steps


The Google Groups to Microsoft 365 Shared Mailbox migration is supported by the Mailbox License and User Migration Bundle (UMB) license types.

Purchase licenses by following the steps below.

  1. Sign in to your BitTitan account. 

  2. In the top navigation bar, click Purchase.

  3. Click the Select button and choose the license type you need.

  4. Enter the number of licenses you want to purchase. Click Buy Now.

  5. Enter a Billing address if applicable.

  6. Click Next.

  7. Review the Order Summary and enter a payment method.

  8. Click Place Your Order.

​​Licenses are released once payment has been received:

  • Licenses are available immediately upon payment via credit card.

  • If you purchase via wire transfer (100+ licenses), licenses are available once payment has been received and accepted.

  • We do not accept purchase orders, because of processing overhead.

In both cases, you will be notified by email that payment has been accepted and licenses will be available in your account upon notification.

For more information on licensing, including coupon redemption and other licensing types, see our Licensing FAQ.

Set Up a Mailbox Migration project

  1. Click Go To My Projects from the MigrationWiz dashboard.

  2. Click Create Project.

  3. Select a Mailbox migration type. 

  4. Click Next Step.

  5. Enter a project name and select a Customer from the list. If you want to add a new customer you can do so here. To create a new customer:

    1. Click New.

    2. Provide required details including primary email domain and company name.

    3. Click Save.

  6. Click Next Step.

  7. Select the Google Groups endpoint from the source drop-down menu.

    • If an endpoint has not been created:

      1. Click New.
      2. Enter a name in the Endpoint Name field.

      3. Select Google Groups from the Endpoint Type drop-down menu.

      4. Upload the JSON file for your service account setup.

      5. Provide a valid super administrator email address for the G Suite account that matches the end user domain.

  8. Select the Office 365 destination endpoint from the destination drop-down menu.

    • If an endpoint has not been created:

      1. Click New.
      2. Enter a name in the Endpoint Name field.

      3. Select Office 365 from the Endpoint Type drop-down menu.

      4. Select Provide Credentials or Do Not Provide Credentials as needed.

        1. If you select Provide Credentials, the form expands to show more fields for username and password. MigrationWiz uses the credentials to access the service chosen. In most cases, you must provide credentials for an administrator account on those services, as this will enable MigrationWiz to have full access to the cloud service.

        2. If you select DO NOT Provide Credentials, MigrationWiz requests credentials from end users before a migration can be started. This may slow your migration, as you are now dependent on end users to provide these credentials.

  9. Complete the Application (client) ID and the Directory (tenant) ID fields, otherwise, you cannot save your project.

    Destintation Settings.png

  10. Click Save, Go to Summary then click Save Project.


When configuring the destination endpoint, do not forget to complete the client ID and the tenant ID fields for the Destination endpoint, otherwise, you cannot save your project migration.

Once the information has been provided for both, the source and/or destination endpoint, and the customer selects Save and Go to Summary, MigrationWiz performs an endpoint validation check for the Microsoft 365 endpoint.

This validation tests the administrator credentials entered into the project and the Modern Authentication setup only. If there is an issue, the screen redirects to the endpoint and provides an error message or flyout that can be selected for more information regarding the error.

Common Errors when Configuring Your Endpoint

For more information, review the AADSTS700016, AADSTS90002, and ADDSTS50126 issues on the Common Errors Using Modern Authentication page.

Add Accounts (Items)

Add the accounts that will be migrated, which are also referred to as items, to a project using one of the following options:

Quick Add

This option allows you to add items one at a time. To do so, you only have to provide an email address if you entered administrative credentials when setting up the project. If you did not, enter the following user information:

  • An email address
  • Login name
  • Password
  • Mailbox status
Bulk Add

Bulk Add uses a CSV containing the source and destination email addresses for the users to add the users to the project. If migrating only a specific group from a tenant, we recommend using the Bulk Add option.

MigrationWiz allows you to bulk import mailboxes into the system.

To import one or more mailboxes:

  1. Sign in to your MigrationWiz account.
  2. Select the Project for which you want to perform the bulk import.
  3. Click Add.
  4. Click Bulk Add.
  5. Follow the instructions on the page.

​Autodiscover process within MigrationWiz can be used to discover items from the Source environment so that they can be imported into your projects. You can edit the project to remove users not being migrated. All users are added with the source and destination email addresses set to match the source email.

Use the Change Domain Name button at the top of the project page to change the domain name. If the usernames change during the migration, we recommend using the Bulk Add option.

There are a few requirements for this to work:

  • The Source has to be Exchange 2007 or later.
  • The endpoint on the Source needs to use admin credentials.
  • For mailbox migration projects, the admin account that is specified within the Source endpoint needs to have a mailbox associated with it.
  • The admin mailbox must be listed in the public Global Address List (GAL).

One additional item to note here is that there is no way to restrict the IP addresses that the connection will come from.  This means that the steps outlined in our IP Lockdown guide will not apply here. If your environment requires that any IP addresses be whitelisted, it is recommended that items be added to your project using one of the other available options.

Autodiscover of items will not work while using Modern Authentication

Autodiscovery exposes the following items:

  • For mailbox migration, autodiscovery will list all mailboxes at the Source.

Steps to Run Autodiscover

  1. Navigate to the project you want to import users into.

  2. Ensure that you have created an endpoint for the source project.

  3. Once in the project, click the Add drop-down on the top navigation bar, then select Autodiscover Items. This will begin the Autodiscover process.

  4. Once discovered, click the Import button, to import the items into your MigrationWiz project.

Advanced Options

The following advanced options may be useful for your migration. 

Support Tab

  • RecipientMapping  Use this advanced option to map the source email addresses to the destination. The right part is a RegEx applied to the recipient's email address. You can use more than one remapping expression.

  • VaultPollTimeoutInMilliseconds=86400000 This will increase the Google Vault polling from 1 hour to 24 hours.
  • UseHashMapRecipientMapping Use this advanced option together with Recipient Mapping to increase performance when mapping large numbers of recipients

  • ModernAuthClientIdImport - Modern authentication client ID support for tenants not using legacy authentication (basic authentication). You would have to set up the app in your AAD portal to get the client and tenant ID. Authentication Methods for Microsoft 365 (All Products) Migrations

  • ModernAuthTenantIdImport Modern authentication tenant ID support for tenants not using legacy authentication (basic authentication). You would have to set up the app in your AAD portal to get the client and tenant ID. Authentication Methods for Microsoft 365 (All Products) Migrations


Default Options

The client and tenant ID fields for the destination in the Support tab of the project’s Advanced Options, are view-only fields. This means that you cannot edit or remove them from the support options page. To edit them,  you need to edit the project.


You cannot update the default Advanced Options, in case you try to modify or add new ones the following message arises.
Duplicate Support Option.png

Verify Credentials

  1. Open the project containing the items you wish to validate.

  2. Select the line items to validate.

  3. Click the Start button in your dashboard.

  4. Select Verify Credentials from the drop-down list.

  5. Once complete, select the Status section and view the results of the verification.

Auto-provisioning of Shared Mailboxes

MigrationWiz now supports the provisioning of Shared Mailboxes for the Google Groups to Microsoft Shared Mailbox migration projects. This is optional for users and does not require any licenses.

Existing mailboxes present at the destination will be skipped. MigrationWiz follows the exact details provided in the destination item information for the provisioned mailboxes 

Steps for Provisioning Shared Mailboxes

  1. Create a Google Groups to Microsoft Shared Mailbox projectmceclip0.png
  2. Input the line items through Quick Add/Bulk Add/ Auto Discoverymceclip1.png
  3. Start a Full migration or Pre-stage migration, and choose the option to provision the Shared Mailboxesmceclip2.png

Performing a Migration

Trial Migration

  1. Select the line items to migrate.

  2. Click the Start button from the top.

  3. Select Trial Migration.

  4. Click Start Migration.

Pre-Stage Pass

  1. Select the line items to migrate.

  2. Click the Start button from the top.

  3. Select Pre-Stage Migration.

  4. Under the Migration Scheduling section, from the drop-down list, select 90 days ago.

  5. Click Start Migration.

Full Pass

  1. Select the line items.

  2. Click the Start button from the top.

  3. Select Full Migration.

  4. Click Start Migration.

Run Retry Errors

Look through the user list and click any red "failed migration" errors. Review the information and act accordingly.

If problems persist, contact Support.

Was this article helpful?
0 out of 1 found this helpful