Copy existing mail to hosting mailboxes
IMAP migration copies messages and folders between mailboxes. It does not automatically migrate contacts, calendars, rules, forwarding or every provider’s labels.
Steps
- Keep the old service active and export an independent backup. Record mailbox names, storage use and any separate contacts/calendars.
- Create destination hosting mailboxes with enough space and secure unique passwords. Confirm the correct source and destination server settings.
- Open IMAPSync Migrations if enabled, or use a trusted IMAP migration client. Use encrypted connections with certificate verification. Enter credentials privately.
- Run a first copy before changing MX. Check folder mapping, date ranges, errors and sample old messages, including attachments. Large mailboxes may need several runs.
- Move MX and mail routing only after the destination is ready. Preserve SPF, DKIM and DMARC requirements for the actual sending services.
- During the DNS transition keep both services available, perform a final incremental copy and test external sending and receiving.
- Export contacts/calendars separately and recreate required rules. Retire the old service only after verifying the data and a usable backup.
Check the result
Compare folders and message counts, then inspect samples; counts alone are not proof of a complete copy. Revoke temporary migration credentials and delete temporary credential files securely.
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Last reviewed
2026-10-28