Import OST to Office 365

Before you import the mailboxes from OST to Office 365, you must prepare the target Office 365 server as described in the following section.

• • 1. 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.
    2. Prepare your target Office 365 tenant. See tenant roadmap for Microsoft 365.
    3. Purchase an Office 365 licensing plan specific to your needs. You can also sign up for a 30 day free trial and decide to go with a suitable one later. Compare Office 365 business plans and Compare Office 365 enterprise plans
    4. Create mailboxes for your users in your organization and assign suitable licenses to them.

         Add users and assign licenses to Office 365 users

         Add several users at the same time to Office 365

         Assign Microsoft 365 licenses to user accounts

    5. If you plan to import Public folders from the OST file into Office 365, ensure that you create and configure the Public folder mailboxes on the target server.

         Create Office 365 Public folder and assign mailbox user

    6. 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
    7. If you have a custom email domain from the source to which you want to receive emails after the migration, you must add and verify the custom domain on Office 365.

        See steps to add a custom domain to Office 365 and steps to add DNS records to connect your domain

    8. Assign the Organization Management role groupin Exchange online to the admin user. It is an elevated permission that is required for mailbox migration.
    9. 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 target admin account in general has the following management roles assigned:
       1. Application Impersonation
       2. View-Only Configuration
       3. View-Only Recipients
       4. Public Folders
       5. User management administrator/Global administrator
    10. Check if the Global admin account with the management roles has a valid and non-hidden mailbox on the target server.
    11. Configure Office 365 to send and receive large messages

         Follow the steps to increase the message size on Office 365 to 150MB.

• Step 1: Download EdbMails OST to Office 365 migration tool
  • Download EdbMails and install the application on your computer.
  • Follow the instructions that appear on screen to complete the installation.

     See a detailed list of EdbMails system requirements, for OST recovery, conversion and migration.

    

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

    

  • Select the migration technique as ‘OST to PST, OST to Office 365 and OST to Exchange’.

    

• Step 2: Select the offline OST file for importing to Office 365
  • Before starting the mailbox import operation, take a copy of the OST file as a backup.
  • Browse and select the OST file from your computer that you want to import to Office 365.

     Tip: EdbMails can repair an Outlook OST file if it has been corrupted, orphaned or is no longer inaccessible. You can directly upload the mail items from OST to O365 without requiring the original Exchange server profile that you configured on Outlook.

    

• Step 3: Preview and select the mailboxes for migration
  • EdbMails first performs a recovery operation and fully restores the OST file in case it is corrupted. You can preview the mail items such as emails, contacts, folders, notes, tasks, calendars from the application’s preview pane. It is also a handy tool if you are looking to open an OST file without Outlook.
  • Select the required mailboxes / folders and click the ‘Migrate to Office 365’ button to continue.
  • Alternatively, you can right click on the selected mailboxes / folders and select the option 'Migrate Selected Mailboxes / Folders to Office 365 Server'.

    

     Tip: EdbMails provides the following additional options to help you customize the mailbox migration to Office 365 based on a Date and other mailbox rules.

    1. Additional Include and Exclude Filter Options
    2. Filter emails by Date: Import emails to Office 365 by applying the Date filter
    3. Filter emails by Size: Exclude emails and attachments from migration, which are larger than a specified size.
    4. Filter emails by domain name: Extract emails sent to and received from a particular domain.

       

  Add a suitable label to the job for identification. This enables you to quickly load the application’s settings for future export operations. You can view all the labels by clicking ‘View Log’ that contains all the details of the previous operation.

• Step 4: Connect to the target server and upload the OST to Office 365
  • In the Connect to Office 365 (Target) window, select the authentication method as Auto or Manual registration for modern authentication and the connection method as Mailboxes, Public folder or Archive Mailbox.
  • Enter the global administrator credentials to authenticate.

      Assign Microsoft 365 licenses to user accounts

    

  • 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.

    

    Note: If the Standard folders (such as Inbox, Calendar, Contacts) in the source EDB file 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: When migrating a source Inbox folder with the name ‘Boîte de réception’ in the French language directly to the destination server, it will not be automatically mapped to the ‘Inbox’ folder on the target server. To ensure proper mapping of the folder with the French name, you must change the regional settings on the target server to match the language of the source mailbox folder, which in this case is French.

      See how to change the language and regional settings on Office 365

     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 enables you to automatically match and map the mailboxes and folders between the source and target and saves time when you’re migrating a large number of mailboxes. Perform the mapping and start the import operation to Office 365.

    

  • That's it! During the migration, you can view the progress, pause and resume the operation, as shown. An appropriate message will be displayed upon completion.
  • Verify the list of migrated folders and mailbox items with EdbMails text-based log report.

     Tip: If you want to export Outlook emails to your computer, learn how to backup Outlook emails to an external hard drive by converting OST to PST files.