📥 Mailbox Migration Guide

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This guide explains how to migrate a mailbox from one email provider to another using the Mail Archiver application.

📋 Overview

The Mail Archiver application provides functionality to migrate emails from a source mailbox to a target mailbox. This is particularly useful when changing email providers while preserving your email history. The folder structure of the source mailbox is also preserved during migration.

Migrating only recent mail? The flow described below copies the whole archived mailbox, and running it twice appends everything a second time. If the new mailbox should hold only mail newer than a cutoff while the full history stays in the archive, use the date-windowed offload instead. It takes a date window, can exclude and rename folders, offers a dry run, and is safe to repeat because it skips whatever the target already holds. It is also driveable from the command line, which makes a fleet of mailboxes scriptable.

🚀 Migration Process

Follow these steps to migrate your mailbox:

1. Add the source account
2. Navigate to the "Email Accounts" section
3. Click "Add Account"
4. Enter your source account details and credentials

5. Save the account

6. Synchronize the source account

7. Allow the application to synchronize all emails from the source account

8. Wait for the synchronization process to complete

9. Add the target account

10. In the "Email Accounts" section, click "Add Account"
11. Enter your target account details and credentials

12. Save the account

13. Synchronize the target account

14. If the target account is new, synchronize it to ensure it's properly set up

15. Wait for the synchronization process to complete

16. Initiate the migration

17. In the "Email Accounts" section, identify the source account
18. Go to the account details
19. Select "Copy All Emails to Another Mailbox" option
20. Choose the target account and a target folder
21. Enable the "Preserve Folder Structure" option – the selected target folder then serves as the root under which the entire source folder structure is recursively recreated
22. If this option is not enabled, all emails are placed directly into the selected target folder (flat, without subfolders)

23. Start the migration process

24. Monitor the migration

25. If there is a large number of emails, the migration will be carried out as a background task
26. The status and progress of the migration can be viewed in the "Jobs" tab

27. Wait for the migration to complete successfully

28. Disable the source account

29. After the successful transfer, go back to the source account
30. Set the source account to "Disabled" in the account settings
31. This ensures that it will no longer be archived in the future

⚠️ Important Notes

• This flow is not repeatable: running it again appends every message a second time. The date-windowed offload is the repeatable alternative.
• Ensure that the source account has sufficient permissions to read all emails
• Make sure that the target account has sufficient storage space for the migrated emails
• The migration process may take some time depending on the number of emails and the connection speed
• It is recommended to perform the migration during off-peak hours to minimize the impact on the email service
• Regularly check the migration status in the "Jobs" tab to ensure the process is progressing
• After migration, verify that all emails have been successfully transferred to the target account

✅ Best Practices

• Always test the migration process with a small subset of emails before migrating the entire mailbox
• Keep a backup of important emails before starting the migration
• Schedule the migration during a time when email usage is minimal
• Monitor the migration progress closely and be prepared to address any issues that may arise
• After the migration is complete, verify that all emails are correctly transferred and accessible