Archive mailbox to Microsoft 365 migration

I. Planning a migration from Office 365 archive mailbox

1. Take a complete backup of all the archive mailboxes before you attempt the migration.
2. Ensure that you create and enable the In-Place Archiving in Office 365 before you migrate. See steps to enable online archive in Office 365.
3. Determine whether you want to migrate the Archive mailboxes to Office 365 primary mailbox or Archive mailbox.
4. If you want to migrate the Archive mailbox directly to Office 365 Archive mailbox, enable the auto-expanding archiving feature on Office 365.
5. By default, the Archives have 100GB of storage when you enable them and the auto-expanding adds additional storage (unlimited archiving) when the threshold is reached. This limit is expandable up to 1.5TB per mailbox.
6. Verify if your Exchange online mailbox license allows the archiving feature.
7. See the list of auto-expanding archiving restrictions and consider the following points for all users.
8. If you would like to learn more about archiving, see how the auto-expanding archiving works.
9. Unlimited archiving is a premium feature that requires Exchange online plan 2 or Exchange online archiving license.
10. Perform a test migration to the target before you start the actual one.

II. Pre migration activities for O365 Archive mailbox migration

1. Ensure that you meet the network and bandwidth requirements for the migration. See performance factors and best practices for Office 365 migration.
2. Prepare your target Office 365 tenant. See tenant roadmap for Microsoft 365.
3. If you plan to migrate In-Place archives to Office 365, enable the archive mailbox on the target server. See steps to enable online archive in Office 365.
4. Assign the Organization Management role group in Exchange online to the admin user on both the source and the target.
5. 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
6. Check if the Global admin account with the management roles has a valid and non-hidden mailbox on the source and target server.

III. Migrate Office 365 Archive mailboxes to Office 365

There are two methods to migrate archive mailboxes to Microsoft 365 by using EdbMails.

1. Direct migration of Archive mailboxes to Office 365
2. Import mailboxes from the PST file to Office 365

Steps to migrate Archive mailboxes to Office 365

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

  • Download EdbMails and install the application on any computer that is connected to the source and target environment. You can also perform the migration operation by installing EdbMails on a 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) in the 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 Archive Mailbox (In-Place Archive). Enter the 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.

   Tip: With EdbMails, you can also migrate Public folder to Office 365 shared mailbox and migrate Groups to Office 365.

• Step 3: Select the mailbox items and then connect to target Office 365
  1. EdbMails displays the archive mailboxes from the source tenant
  2. Select the mailboxes and folders that you want to migrate.
  3. Click 'Migrate to Office 365' to set up 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 and migration settings for mailboxes.
  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 target server as Global Administrator

  EdbMails supports both modern and classic authentication. Connect to the target server by selecting Auto or Manual registration for modern authentication. You can migrate an Archive mailbox to Archive or to the primary mailbox on your target Office 365 tenant.

   Connect to Office 365 server using secure modern authentication

• 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 tenant and Office 365. This activity saves time when you’re migrating a large number of mailboxes.

  

• Step 6 : Start the Office 365 Archive mailbox migration

  Start and monitor the migration after you complete the mailbox mapping. You can pause and resume the migration and an appropriate message will be displayed on completion of the operation. Finally, verify the count of migrated emails, folders and mailbox items with EdbMails text-based log report.

Migrate Archive mailboxes to Office 365 with PST import

EdbMails can also assist you in migrating archive mailboxes to Office 365, if you have them exported as PST files. Download EdbMails if it is not installed in your machine and launch the application. The following steps outline how to import PST files to Office 365.

• Step 1: Select the migration method as Office 365 migration

  On the EdbMails migration selection popup, select the migration technique as Office 365 migration.

• Step 2: Add PST files in bulk to migrate to Office 365

  To add the PST files, close the Connect to Office 365 (Source) connection window and click 'Migrate PST to Office 365' at the bottom. Add single or multiple PST files and continue.

• Step 3: Connect to target Office 365 as Global Admin User

  EdbMails supports both modern and classic authentication. Connect to the target server by selecting Auto or Manual registration for modern authentication and the connection method as Archive Mailbox.

  

   Connect to Office 365 server using secure modern authentication

• Step 4: Map and migrate mailboxes and folders to Office 365

  The mapping activity in EdbMails can automatically match and map the mailboxes and folders from the PST file to Office 365. This activity saves time when you’re migrating a large number of mailboxes. After you complete the migration, verify the count of the migrated items, folders and mailboxes with the help of EdbMails log report.