Office 365 to G Suite Migration Guide


This migration guide contains the necessary steps to perform the actual migration, but there are many steps to preparing for migration. 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 already completed the migration preparation, simply follow the steps below.

To discover what items are moved with MigrationWiz in this scenario, and which items will not be moved, see Moved Items. Note that these items will vary by source and destination, so check the proper environment listings carefully.

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.

We are not able to support migrations with two-factor or multifactor authentication. 


Preparing the Source

Create Global Administrator Account

Create a Global Administrator account in Office 365 to be used for migration or use the Global Administrator account for the tenant. In order to have administrative permissions to migrate mailbox data, grant the account permissions on each mailbox.


  • Having administrative access to the Microsoft Office 365 control panel to manage users does not mean the same account has permissions to access all mailboxes for migration.
  • Having delegated admin access to accounts does not provide enough access.

Enabling an administrative account the ability to access Office 365 user mailboxes can be performed by adding the Impersonation role or Full Access mailbox permissions.  The below steps will explain how to configure the permissions access for both options.


To enable the admin account to impersonate users, run the below PowerShell commands:

$cred = Get-Credential

$session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri -Credential $cred -Authentication Basic -AllowRedirection

Import-PSSession $session


New-ManagementRoleAssignment -Role ApplicationImpersonation -User <admin_user_name>

Remove-PSSession $session

More information about this PowerShell command can be found here.


  • MigrationWiz uses delegation by default to log in to individual user mailboxes using administrative credentials specified on the connector. 

It is highly recommended to use impersonation when migrating from or to Office 365.


Using impersonation, it is possible to stop sharing the throttling quota and connection limits associated with a single administrative account. Instead, the throttling quota of each user is used to log in to each user mailbox.

Using impersonation means:

  • Eliminating most "Connection did not succeed" errors
  • Allowing migration of more mailboxes concurrently
  • Reducing the impact of throttling and connection limits
  • Using an admin account without assigning a license to it

Full Access

To manually grant administrative access for migration, execute the following remote PowerShell commands: 

$cred = Get-Credential

$session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri -Credential $cred -Authentication Basic -AllowRedirection

Import-PSSession $session

Get-Mailbox -ResultSize Unlimited | Add-MailboxPermission -AccessRights FullAccess -Automapping $false -User MigrationWiz

Remove-PSSession $session


  • The command needs to be applied each time a new mailbox is created since permissions are set directly on each mailbox. The administrative account will not have access until the permissions are applied.
  • In the script above, the username "MigrationWiz" should be replaced with the name of the administrative account that was set up, by following the instructions in this Knowledge Base article.
  • This username is the Administrative Username that needs to be entered under the project's Source or Destination settings, within MigrationWiz, when checking the box labeled Use Administrative Login.

Preparing the Destination

For this scenario, the Google IMAP or the API endpoints may be used. 

Google IMAP

Grant MigrationWiz OAuth 2.0 Access

Grant MigrationWiz OAuth 2.0 access to G Suite. If you are migrating to multiple domains, repeat these steps for each domain.

BitTitan products use OAuth 2.0 to authenticate to G Suite  and utilize the G Suite (IMAP) endpoint in MigrationWiz. This is applicable to both mailbox and document migration projects. In order to obtain access to your G Suite data, it is necessary to add specifically allowed API scopes to the MigrationWiz project. Enabling access is required for both G Suite mailbox and Google Drive document migration projects.

Mailbox migration projects require that a G Suite administrator grant access to the BitTitan client ID and scopes listed in this article.

The following section will explain how to configurate the OAuth access within your G Suite environment.

OAuth Configuration: Steps in the G Suite Admin Console

Complete these steps to grant BitTitan client ID access to the appropriate scopes:

  1. Go to authenticate as a Super Administrator.
  2. Click Security. If you do not see the security icon on your admin console home page, you do not have the necessary rights on your account to make these changes. Request Super Administrator access from the customer to implement these changes.
  3. Click Advanced settings. Google limits accessing and changing this setting to only G Suite Super Administrator accounts.
  4. Click Manage API client access.
  5. Enter 113321175602709078332into the Client Name 
  6. Enter the following group of scopes into the One or More API Scopes
  7. Click Authorize.
  8. The client name is 113321175602709078332(make sure there are no leading or trailing spaces, as this may cause the error "URL ends with an invalid top-level domain name."). This will grant BitTitan products access to the appropriate scopes.

Enable APIs and Whitelist MigrationWiz as a Trusted App

  1. Go back to Security.
  2. Click API Permissions.
  3. Verify that all options listed are marked Enable. If there are any not enabled, click Enable for those items and click Save.
  4. Click Trusted Apps.
  5. Click the + () button to Whitelist an app.
  6. Select Web Application from the drop-down menu.
  7. Enter 113321175602709078332 for the OAuth2 Client ID.
  8. Click Add.
Google API

Using the Google API for migration allows mailboxes to be migrated even when IMAP is disabled on the Google tenant. IMAP is often disabled for security reasons, which has historically prevented migration through MigrationWiz.

Using the Google API will also increase throughput for the migration and support increased security on the tenant.


  • 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.

Step 1: 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.

 Step 2: Enable APIs for Service Account

  1. From the Google Cloud Platform Console, click Menu (Google_Menu.png) > APIs & Services > Library.
  2. Enable the following APIs by selecting the specific API and clicking Enable. Repeat for each API:
    • Google Drive API
    • Google Calendar API
    • Gmail API
    • Contacts API
    • Admin SDK
      Note: Make sure that the Gmail, Calendar, and Contacts services are enabled within the Google tenant. You can control services for your users using the instructions on this page: Control who can access G Suite and Google Services.

Step 3: Create Customer Tenant Service Account

  1. From the Google Cloud Platform Console, click Menu (Google_Menu.png) > 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 Dropdown menu.
  5. Click Continue.
  6. Click + Create Key.
  7. Make sure that JSON is selected and click Create.
    • 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.
  8. Click Done.

Step 4: Setting the Scopes for the migration

  1. From the Google Cloud Platform Console, click Menu (Google_Menu.png) > IAM & Admin > Service accounts.
  2. Find the service account that was set up in Step 3.
  3. Find the Unique ID field for that service account and copy the ID number. This is the Client ID number that will be used in a later step.
    • This field often needs to be added to the view. Click on the Column display options button (UniqueID2.png) and add a checkmark to Unique ID, then click OK.
    • This Client ID should be considered similar to Administrator account passwords and handled securely.
  4. Go to the G Suite admin page at and click on Security > Advanced Settings > Manage API Client Access.
  5. In the Client ID field, paste the Unique ID copied in step 5.
  6. In the One or More API Scopes field, paste all scopes listed below:,,,,,,,,,
  7. Click Authorize.

You should now see your specific Unique ID and the scopes listed, similar to what is shown below:



Step 5: Set up the Google API endpoint during project creation

During the project creation process, click New for the Destination Endpoint.
2. From the dropdown menu, select G Suite (Gmail API).
3. Click Select File.
4. Navigate to and select the JSON file that contains the Google Service Account key that was saved during the service account setup process.
5. Enter the administrator email address.
6. Click Add


Licenses are required to run a migration project in MigrationWiz. To obtain license pricing information, or to purchase licenses, click the Purchase button in the top of your MSPComplete or MigrationWiz dashboard.

Payment: We accept credit cards, and wire transfer in certain situations.  

  • When purchasing with a credit card, payment is immediately processed during checkout. If successful, licenses are granted to your account instantly.
  • Wire transfers are available for purchases of 100 or more licenses. If you are purchasing at least 100 licenses, you will be presented an option to purchase via wire transfer during checkout. A wire transfer checkout will generate an invoice with wiring information for your accounts payable department and bank. Once the funds are received by our system, the licenses are granted to your account immediately. 

For this project type it is recommended to use our User Migration Bundle licenses. 

  1. Sign in to MigrationWiz at
    • You can either sign in and make sure to select the MigrationWiz button above the email field or sign into MSPComplete page, then click the All Products button and select MigrationWiz.
  2. Select the correct workgroup on the top of the left navigation pane. This is the workgroup that the customer and migration project were created under. Your account must be part of the workgroup and project sharing must be enabled, if the project was not created under your account.
  3. Click the project that requires licenses to be applied.
  4. Check the box to the left of the email for the user(s) to whom you want to apply a User Migration Bundle license.
  5. Click the More menu (3 stacked lines) at the top of the project page.
  6. Click Apply User Migration Bundle License.

Create A Project

Create a Mailbox Migration Project

  1. Click Go To My Projects
  2. Click Create Project
  3. Select a Mailbox migration type. Mailbox projects are used to migrate the contents of the primary user mailbox from the previous environment to the new environment. Most mailbox migrations can migrate email, calendars, and contacts.
  4. Click Next Step.
  5. Enter a Project name and select a Customer.
  6. Click Next Step.
  7. Select a Source Endpoint from the Endpoint drop-down menu. If an Endpoint has not been created, click New and provide the requested information in the Endpoint creation flyout window.
  8. Select a Destination Endpoint from the Endpoint drop-down menu. If an Endpoint has not been created, click New and provide the requested information in the Endpoint creation flyout window.
  9. Click Save and Go to Summary.

Add Accounts (Items)

Add the accounts that will be migrated, 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. You have to enter an email address, login name, and password for each user if you didn't enter administrative credentials when setting up the project. You only have to provide an email address if you entered administrative credentials when setting up the project.
  • Autodiscover Items: MigrationWiz detects the mailboxes directly at the Source using 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, on the top navigation bar, click on the Add drop-down, then select Autodiscover Items. This will begin the Autodiscover process.
    4. Once discovered, click on the Import button, to import the items into your MigrationWiz project.
  • 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.
    1. Select the Project for which you want to perform the bulk import.
    2. Click on Add.
    3. Click on Bulk Add.
    4. Follow the instructions on the page.

Set Advanced and Support Options

Advanced Options allow you to choose your notifications, filtering, maintenance, licensing, performance, and some configuration options.

Support Options are advanced configurations that make use of Powershell or code blocks to provide extra options or resources for your migration.

The following options are the most valuable for this migration scenario:

Set the Project Advanced Options.

  • Set impersonation to be used at the Source. In the Advanced Options, check the Use impersonation at Source box. 
  • Under Support/Support options add: 
    FolderMapping="^INBOX/->" under Support/Support options.
    This will map folders to the root label on the Destination mailboxes, rather than under inbox/labelname. 

Setting Endpoints

  1. When creating the project on your Source Settings or Destination Settings tab, click New.
  2. Fill in the fields. Once the endpoint has been saved in the project, it will automatically be assigned to the customer that was selected in the Project Information tab when creating the project.
    • Name: Type any name you want for the endpoint.
    • Find My Service Provider: Use this control only if the endpoint you’re creating is hosted by a service provider and not a local endpoint. If you don’t know your server type, click this button and then click your provider in the drop-down list.
    • Endpoint Type: Click the Endpoint Type drop-down, and then click the appropriate endpoint type in the list. Ensure you have selected the correct source and destination. When you select an endpoint type, the form will expand so that you can provide additional connection information and credentials for that endpoint type. These additional fields vary depending on the endpoint type.
    • If an endpoint does not exist for the service that you want to connect to with MigrationWiz, then use the Generic endpoint type to generically store the web address for that service, a username, and password. This endpoint can still be used for Runbook execution.
    • Provide credentials: Select Provide Credentials or Do Not Provide Credentials as needed.
    • 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.
    • If you select Do not provide credentials, then MigrationWiz will request credentials from end users before a migration can be started, or before a Runbook can be completed. This may slow your migration, as you are now dependent on the end users to provide these credentials.
    • Domains: For migrations using G Suite Endpoints, this is the list of domains that you will be migrating to, or migrating from. This is not relevant to any other migration environment.
    • Use SSL: For some endpoint types, there is an SSL check box at the bottom of the form. Select this check box if you want to secure your new endpoint with Secure Sockets Layer (SSL).
    • If your provider does not use SSL, do not select this check box, and enter the non-SSL port number in the field provided. For IMAP endpoints, the default port number for non-SSL is 143. For POP endpoints, the default port number for non-SSL is 110.

Run Migration

The following sections will guide you through setting up and launching your migration. Each header is one step, with its component steps below. Follow these steps in order, and read the notes for important information about dependencies or best practices.

Run Verify Credentials

  1. Open the Project containing items you wish to validate.
  2. Select the items you wish to validate.
  3. Click on the Start button in your dashboard.
  4. Select Verify Credentials from the drop-down list.
  5. Once complete, the results of the verification will be shown in the Status section.

Notify Users

Send out the final notification that the migration is beginning. Include when the migration will start, expected duration, any usage instructions during migration, and any expected steps or notifications for the post-migration timeline.

If using DeploymentPro, we have provided some sample text and screenshots that can be included in this email.

Pre-Stage Pass

  1. Select the users
  2. Click the Start button from the top, and select Pre-Stage Migration 
  3. Under the Migration Scheduling section, from the drop-down list, select 90 days ago
  4. Click Start Migration

MX Record Cutover

Change over MX records on the DNS provider's portal. Also, include the AutoDiscover (CName) setting. There are several options for this, based on the size of your project.

Small Projects

Manually set forwards during a migration on a per-user basis, from the individual users' portal. This is only a valid option for a small number of users. Forwards are useful if you are migrating users in batches, and switching some users over to the new Destination before others. Forwards allow for mail coexistence, but not for calendar free/busy coexistence.

  1. Sign in to your account.
  2. Click on Settings.
  3. Locate the Forwarding and POP/IMAP tab.
  4. Click Add a forwarding address.
  5. Enter the email address to forward to.
  6. A confirmation email will be sent to the forward mailbox.
  7. Validate the confirmation by logging in to the forward mailbox.
  8. Go back to your account.
  9. Select the forward mode.

We recommend not saving a copy locally, because when you migrate the mailbox to the destination, you will end up with duplicates.

Medium Projects
Manually set forwards during a migration on a per-user basis, from the admin portal. Forwards are useful if you are migrating users in batches, and switching some users over to the new Destination before others. Forwards allow for mail coexistence, but not for calendar free/busy coexistence.
  1. Sign into your control panel.
  2. Click on the Organization & users menu.
  3. Click on the user you wish to provide coexistence for.
  4. Scroll to the bottom of the User information section.
  5. Click on the link Add another destination. A new row should have been added.
  6. Enter the email address of the new mailbox to coexist with. This email address needs to be different than the email address in your source
  7. Make sure both checkboxes are selected (they already are, by default). There is one in front of the row and another under the column called Change SMTP envelope.
  8. Unselect the checkbox in front of the row.
  9. Click on Save Changes.
Large Projects
Automate the setup of mail coexistence (forwards) for GoogleApps through the MigrationWiz management console tool. The BitTitan Management Console is part of the BitTitan PowerShell, which can be downloaded and installed by following the instructions in the How do I install the BitTitan SDK? article. Complete the following prerequisites before adding the forwarding addresses:
  1. Create a subdomain of your primary vanity domain, and add that subdomain to the Destination environment. For example, if your vanity domain is and the Destination is Office 365, create the subdomain and add it to Office 365 for Exchange Online.
  2. Make sure that all the users at the Destination have a secondary address for the routing subdomain you are using. For example, should be a secondary SMTP address of John's account at the Destination.
  3. Add the appropriate MX record to ensure that all email sent to the subdomain is routed to the Destination environment. Before implementing the forwarding addresses, test the mail flow by sending an email to the forwarding address (for example, and confirming that it is delivered to the Destination.
  4. Make sure you have the MigrationWiz project configured correctly with the admin's email address and domain configured in the Source connector.
  5. Navigate to %UserProfile%\AppData\Roaming\BitTitan and, if it is present, delete the GoogleOAuthDataStore file. This is to eliminate any Google caching from interfering.
  6. Log in to your tenant with the admin's account from your browser.

If you are migrating in batches, you will not be cutting over the MX records until your final batch of users has been migrated.


If Mail Coexistence if Required

If mail coexistence is required, you must set up mail forwards against those user accounts that are in the migration batches. Google documentation explains how. 

Run Full (Delta) Pass Migration

Select the users – you may either select individual users, or select all users in a project by clicking the checkbox to the left of Source Email.

Click the Start button from the top

Select Full Migration. If you want to delay your migration, then select the checkbox marked "Automatically start the migration at", and enter the date and time to have the migration start. To start a migration immediately, you do not need to select the scheduling option.

Click Start Migration

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 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), has been deleted or moved, or if the item failed again.

Run Final Full Migration Pass

  1. Under Project Advanced Options, navigate to filtering section
  2. Delete:  (^All Mail$|^All Mail/)
  3. Select the users
  4. Click the Start button from the top, select Full Migration
  5. 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.

If users will be using Microsoft Outlook with G Suite, they will need to follow the instructions here, to download and install G Suite Sync for Outlook and create a new Outlook profile that connects to G Suite. Click the bar chart icon in the MigrationWiz dashboard to receive an email containing all the project migration statistics.

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