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 in order 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.

  • Groups 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 another Groups will not be migrated.

  • Conversation tags like “Star”, “Abuse”, “Report”, “Locked” are not migrated due to 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”, “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 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 it’s original conversation thread format.

    • To prevent encountering this issue, choose one of the following:

      • Utilize the Advanced Option UseMultiAdmin=1, or,

      • User should set “Advance Option>Performance>Maximum number of concurrent migrations” to 3, or

      • User should 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.

Which Items Are and Are Not Migrated

What is migrated

  1. Google Groups Members

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

  2. Google Groups conversation

    1. Conversation metadata

    2. Conversation attachments

    3. Conversation labels

What is 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”, “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 be enabled. 


  • Subscription to Google Cloud Platform

  • Google Super Administrator account

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

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

  • 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. From the Google Cloud Platform Console, click Menu () > APIs & Services > Library.

  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 Customer Tenant Service Account

  1. From the Google Cloud Platform Console, click Menu > IAM & Admin > Service accounts.

  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 right upper 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 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 Unique ID

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






  8. Click Authorize.

Assigning Google Vault privileges

  1. 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, click Continue

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

    1. Manage Matters

    2. Manage Searches

    3. Manage Exports

    4. 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

Exchange Online EWS Modern Authentication Requirements (click on this box to expand required steps)

The steps listed below apply to both the source and/or 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.


For setup steps that include images, see under Enabling Modern Authentication for EWS between MigrationWiz and your Exchange Online Tenant in the following KB: Authentication Methods for Microsoft 365 (All Products) Migrations

Important: Failure to perform the steps for your Microsoft 365 endpoints, can result in failed jobs with 401 errors like the following in your project: Http POST request to '' failed - 401 Unauthorized

The administrator account being used for the project needs to be excluded from any MFA/2FA policies or Conditional Access policies that can block access for the administrator account. This requirement does not apply to the items or users being migrated in the project.

Configuring Modern Authentication to work with MigrationWiz for mailbox, archive mailbox, and public folder projects in Exchange Online is now the default method after Microsoft discontinued support for Basic Authentication in Exchange Online after December 2022. The following Microsoft documentation outlines this change in more detail. Should you have additional questions on how this change may impact your tenant, please contact Microsoft to assist with providing that information: Deprecation of Basic authentication in Exchange Online

The Azure Security Defaults must also be disabled in the tenant. (This is often enabled by default for all new Exchange Online tenants and there is no workaround for this requirement). For steps on where to enable/disable the Azure Security Defaults, see Enabling security defaults in the following Microsoft documentation. To disable, set Enable Security defaults to No: Security defaults in Azure AD

Modern Authentication Steps
  • Log in to the Azure AD admin console with a Global Administrator login.
  • Select Azure Active Directory in the Azure Active Directory Admin Center.
  • Select App Registrations, which is found under Manage.
  • Select New Registration at the top of the screen.
  • Give the app a distinct name. You can change this later if necessary.
  • Select the Accounts in any organizational directory button.
  • Under Redirect Uri, select Public Client (mobile & desktop) and set it to urn:ietf:wg:oauth:2.0:oob
  • Click Register.
  • Go back to App registrations.
  • Select the App you just created.
  • In the Overview, you will find a ClientId (aka Application) and Directory (Tenant) ID.
  • Copy both of these to another application, such as Notepad, for use later in this process.
  • Under the Manage menu, select Authentication.
  • Set the option Allow public client flows to Yes
  • Click Save.
  • From the Manage menu, select API permissions.
  • If API permission named User.Read under Microsoft Graph is already present, this can be removed. The Microsoft Graph API is not applicable to this project type and is not used.
  • Select Add a Permission.
  • Select APIs my organization uses

  • Scroll down and select Office 365 Exchange Online

  • Then select Delegated Permissions

  • Select EWS

  • Check the box under EWS for EWS.AccessAsUser.All.
  • Click Add permissions. This permission only allows the OAuth application (MigrationWiz) to be associated with EWS.
      • Important: This does not grant access to all mailbox data.
  • Click Grant admin consent.
  • Click Yes to confirm the settings.
  • In MigrationWiz, select the project that needs to be configured for Modern Authentication.
  • Click the Edit Project menu.
  • Select Advanced Options.
  • Under Support Options enter the ClientID and TenantID information you saved earlier in the following format:
    • If enabling Modern Authentication for the Source:
      • ModernAuthClientIdExport=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
      • ModernAuthTenantIdExport=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
    • If enabling Modern Authentication for the Destination:
      • ModernAuthClientIdImport=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
      • ModernAuthTenantIdImport=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx 
        • Enter the specific ClientID and TenantID for your tenant in place of the xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
        • These options can be entered for either the Source or the Destination, or both, depending on the settings on the tenants.
        • These options need to be configured for each MigrationWiz project that needs to have Modern Authentication enabled.

  • Run a Verify Credentials to confirm that MigrationWiz can connect using Modern Authentication. 
  • Click on the item that was verified. There will be a message in the MigrationWiz Migration Information page that Modern Authentication is being used. This message will show in the “Migration Errors” box; however, it is not an error. This is just a message confirming that Modern Authentication is now active and being used for the connection.

MigrationWiz Steps


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

Purchasing a license

To purchase licenses:

  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:

  • If you purchase via credit card, licenses will be available immediately upon payment.

  • If you purchase via wire transfer (100+ licenses), licenses will be 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. From MigrationWiz dashboard, click Go To My Projects.

  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.

    1. If the customer hasn’t already been created, you can do so here.

    2. To create a new customer, click New, provide required details including primary email domain and company name, and click Save.

  6. Click Next Step.

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

    • If an endpoint has not been created, click New.

      1. Enter a name in the Endpoint Name field.

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

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

      4. Provide a valid super administrator email address for G Suite account which 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, click New.

      1. Enter a name in the Endpoint Name field.

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

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

        1. If you select Provide Credentials, the form expands to present more fields for username and password. The credentials will be used by MigrationWiz to access the service selected. 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, then MigrationWiz will request credentials from end users before a migration can be started. This may slow your migration, as you are now dependent on the end users to provide these credentials.

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

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 o​ne at a time. Provide an email address for source and destination for each.

  • Bulk Add: This option allows you to add multiple items at once by copying and pasting from a spreadsheet or by importing a CSV file. The domain names at the Source and at the Destination might be different. Make sure to provide the right information in the project. If they are different, it's best to modify these in your CSV file, and then use the Bulk Add feature to import the users into the dashboard.

  • Auto-discover: This option allows you to generate a list of Google Groups as MigrationWiz will automatically discover all the relevant Google Groups available under the Google Administrator provided in the Source setting. Once the discovery process is completed, you can click on “Import Items” or choose to download the CSV file for edits.

Advanced Options

The following advanced options may be useful for your migration. 

Advanced options under Support tab

  • RecipientMapping - Use this advanced option to map the source email addresses to destination. Right part is a RegEx applied to the recipient 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 setup 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 setup the app in your AAD portal to get the client and tenant ID. Authentication Methods for Microsoft 365 (All Products) Migrations


  • UseMultiAdmin=1 - To enable the use of up to 5 multiple administrator credentials in the Source endpoint creation to workaround the inherited PowerShell concurrency limitation of 3 line items per run. With the Advanced Option, this would increase the concurrency up to 15.

    • The Advanced Option must be used for MW to support up to 5 administrator credentials.

    • The first administrator credential is taken as the primary admin and as a reference for domain verification.

    • A comma “,” is to be used as the delimiter for both usernames and passwords.

    • MigrationWiz will automatically trim the trailing and leading spaces for each username and password:

      • (eg, “Adminuser1,Adminuser2 , Adminuser3, Adminuser4 ,Adminuser5”)

    • An error will occur if multiple credentials are used without the Advanced Option, or if there is a mismatch between the number of usernames and passwords.

    • With the Advanced Option, the user should configure “Advance Option>Performance>Maximum number of concurrent migrations” accordingly (Eg, 5 administrator credentials would allow 15 concurrent migrations, instead of 3).


Verify Credentials

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

  2. Select the line items you wish 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 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 you wish 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 you wish 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