This article describes the steps and order to follow to transfer your domain between two Office 365 tenants.
- Before the switch, modify MX record TTL to smallest time allowed.
- Cloudiway configures mail routing between the source domain names and the technical target domain (eg: target.onmicrosoft.com sample:
Source SMTP
Target SMTP
company.com
target.onmicrosoft.com
company2.com
target.onmicrosoft.com
- When you’re ready to switch, modify your MX records to point to the Cloudiway IP.
- Run a final delta pass.
- At this step, new mails arrive to the target and old mails are all migrated to the target. You’re now safe to detach the domains.
- Run the script to remove domain from objects (see script in Move domain)
- Remove Domain from Tenant.
- Add domain to target tenant.
- Add TXT DNS record.
- Verify domain ownership.
- You can now reassign the domains to the users: Modify SMTP and UPN on Target AD and sync the changes.
- Modify your MX records to point to target Office 365.
- The migration is completed.