Office 365 to Hosted Exchange migration

Planning a migration from Office 365 to Hosted Exchange

The most important aspect of the migration is planning. A good plan saves time and makes the operation run smoothly and without stress. Here is a checklist of the most important factors to consider when migrating from Office 365 to Hosted Exchange.

1. Prepare a complete inventory of items that you want to migrate from Office 365.
2. Take a complete backup of all your mailbox items and folders and remove the unused and unwanted mailboxes from the source.
3. Determine if you want to follow the cutover migration method, hybrid or staged migration.
4. Determine if you want to migrate Public folders and Shared mailboxes along with the primary mailbox.
5. Determine the size of the mailbox data and number of mailboxes to migrate.
6. Communicate any changes to your end users and inform the stakeholders.
7. Decide on a suitable Hosted Exchange provider and purchase a mailbox license plan.
8. Prepare the domains and required Active Directory services on the target.
9. Create mailboxes and Public folders on the target Exchange server
10. Ensure you have enough network capacity and bandwidth to migrate.
11. Consider the throttling and message size limits on the source and target.
12. Perform a test (pilot) migration before you start the actual migration.
13. Start the migration, verify the endpoint and add the DNS records.
14. Create new Outlook profiles for the users and check if you are receiving mails correctly
15. Remove the permissions and licenses on the source Office 365 tenant.

I. Pre migration activities for Office 365 to Hosted Exchange migration

• Step 1: Check that you meet the following requirements on Office 365
  1. Assign management roles to the admin user on the source

     Assign the Organization Management role group permission in Exchange online to the admin user. It is an elevated permission that is required to migrate Public folders.

  2. Assign the required impersonation rights

     Set the impersonation rights for the admin account in Office 365 to migrate mailboxes on behalf of other users in your organization.Verify if the source and target admin account in general has the following management roles assigned:

     1. ApplicationImpersonation
     2. View-Only Configuration
     3. View-Only Recipients
     4. Public Folders
     5. User management administrator/Global administrator
  3. Verify the mailbox of the admin account

     Check if the Global admin account with the management roles has a valid and non-hidden mailbox on the source.

  4. Prepare your environment to meet the network requirements

     Ensure that you meet the network and bandwidth requirements for the migration. See network and migration planning, performance factors and best practices for Office 365 migration.

  5. Plan how you want to migrate from Office 365 to Hosted Exchange

     Decide the migration path you want to take depending on your environment. The following table illustrates the three approaches.

     Current environment and requirement	Migration approach	How does the migration take place?
     You want to perform a complete migration to the Exchange server in a single event and in a limited time frame.	Cutover migration	In this approach, you set up your target Exchange server and migrate everything in a single sitting. Suited for large mailbox migration
     You want to perform the migration in phases	Staged migration	In this approach, you migrate your mailboxes and mail data in stages and transfer the required or the most recent data first followed by the others.
     You want to migrate your Office 365 data to an Exchange server that exists in a hybrid environment with another service.	Hybrid migration	In this approach, you migrate from Office 365 to Exchange that coexists with Office 365 or another email service.

• Step 2: Check that you meet the following requirements on the Hosted Exchange
  1. Create mailboxes and Public folders on the Exchange server

     Before you migrate, ensure that you create mailboxes on the target Exchange server and assign suitable licenses to them.

  2. Assign management roles to the admin account

     Set the following permissions to the admin account on the Hosted Exchange.

     1. ApplicationImpersonation
     2. View-Only Recipients
     3. View-Only Configuration
  3. Verify the mailbox of the admin account

     Check to see if the admin account that has been assigned management roles has a valid and non-hidden mailbox on Exchange.

  4. Configure the throttling and message-size limits

     Depending on your Hosted Exchange provider, you may have to change the EWS throttling and message size limits on the Exchange server.

II. How to perform Office 365 to Hosted Exchange migration?

There are three methods to migrate to a Hosted Exchange server

1. Office 365 to Hosted Exchange cutover migration
2. Batch or Staged migration
3. Hybrid migration between Office 365 and Exchange

Steps for Office 365 to Hosted Exchange migration with Cutover method

• Step 1: Download and install EdbMails Office 365 migration software

  • Download EdbMails and install the application on the source computer. You can also perform the migration operation by installing EdbMails on any non-Exchange server computer.

     See a detailed list of EdbMails system requirements for Office 365 migration.

    

  • Launch the application and click 'Login' or 'Start Your Free Trial'.

    

  • Select the migration technique as Office 365 migration

    Select the option 'Office 365 Migration' (Tenant to Tenant migration & more...) from the drop down and click on Let’s Go!

    

  Note: If the Standard folders (such as Inbox, Calendar, Contacts) on your source Office 365 mailboxes are initialized with a different language, follow the details in the link to migrate these folders to the respective system folders on the target (destination) server.

  For Instance: If your source Inbox folder is named 'Boîte de réception', which is in French language and you migrate this folder directly to the destination server, then by default it will not be mapped to the 'Inbox' folder on the target server. In order to map the folder with the french name to the respective folder, change the regional settings on the target server to match that of your source mailbox folder language (in this case, it is French).

   Click here to know the steps to change the language and regional settings on Office 365

• Step 2: Connect to the source Office 365 as Global Administrator

  In the Connect to Office 365 (Source) window, select the authentication method as Auto or Manual registration for modern authentication and the connection method as Mailboxes, Public folder or Archive Mailbox (In-Place Archive). Enter your global administrator credentials to authenticate.

   Connect to Office 365 server using secure modern authentication

  

  

  After you authenticate and log in successfully, select one of the methods to load the mailboxes. You can also load and migrate the mailboxes using a CSV file.

• Step 3: Select the mailbox items and then connect to the Hosted Exchange
  1. EdbMails displays a list of mailboxes from the source Office 365 tenant.
  2. Select the mailboxes and folders that you want to migrate.
  3. Click 'Migrate to Live Exchange' to setup the connection with the target server

  

  Tip: If this is the first time you’re migrating with EdbMails, the migration is a full migration. On subsequent migrations from the same source to the target, the migration is incremental.

  EdbMails provides the following additional options to help you customize the migration task.

  1. Additional Include and Exclude Filter Options
  2. Filter emails by Date: Migrate to Office 365 by applying the Date filter
  3. Filter emails by Size: Exclude emails or attachments larger than a specified size.

  

• Step 4: Connect to the Hosted Exchange server

  In the Connect to Exchange server (Destination) window, select 'Connect to Hosted Exchange Server'. You can also connect to the mailboxes by loading a CSV file or with Full Access permission. See the instructions on how to use the different Exchange server connection methods supported by EdbMails.

  Depending on your Hosted Exchange provider, you can choose to manually connect to the Exchange with the 'Default Connection' or connect directly with the 'Autodiscover email' option.

   With EdbMails, you can migrate mailboxes, public folders, and archive mailboxes from Microsoft 365 to Exchange.

  

• Step 5: Map the mailboxes between the source and the target

  The mapping activity in EdbMails can automatically match and map the mailboxes and folders between the source and the target. This activity saves time when you’re migrating a large number of mailboxes.

  

• Step 6 : Migrate to Hosted Exchange from Office 365

  Start and monitor the migration operation after you complete the mailbox mapping. Finally, verify the count of migrated emails, folders and mailbox items with EdbMails text-based log report.

Microsoft 365 to Hosted Exchange staged migration

The staged migration with EdbMails involves migrating the newest emails and mail items to the Exchange server in the first stage and migrating the remaining mailbox data in subsequent stages or over weeks.

• Step 1: Install EdbMails and connect to the source Office 365 tenant

  Download and install the application and select Office 365 migration. In the connection page, select Auto Registration and connect to the source Office 365.

• Step 2: Select the mailboxes and folders to migrate to target Office 365
  • After a successful login, EdbMails displays a list of mailboxes and folders.
  • Select the mail objects you want to migrate and click 'Migrate to Live Exchange'
• Step 3: Prepare your mailbox data for Exchange staged migration

  EdbMails provides the following additional options to help you perform staged migration based on a Date and other conditions.

  1. Additional Include and Exclude Filter Options and migration settings for mailboxes.
  2. Filter emails by Date: Migrate to Exchange by applying the Date filter
  3. Filter emails by Size: Exclude emails from migration larger than a specified size.

  

• Step 4: Connect to Exchange server as Global Admin User

  In the Connect to Exchange server (Destination) window, select 'Connect to Hosted Exchange Server'. You can also connect to the mailboxes by loading a CSV file. See the instructions on how to use the different Exchange server connection methods supported by EdbMails.

   With EdbMails, you can migrate mailboxes, public folders, and archive mailboxes from Microsoft 365 to Exchange.

  

• Step 5: Map the mailboxes and start the staged Office 365 migration

  The mapping activity in EdbMails can automatically match and map the mailboxes and folders between the source and target server. Start and monitor the migration and verify the count of migrated emails, folders and mailbox items with EdbMails text-based log report.