merging emails

Question

We have our own domain, which we own, and have just set up business 365. We currently have un licensed emails. How can I merge the current email address to be active across 365 accounts?

Answer 1

Hi @Jessie - Project Manager,

Thank you for the additional details.

Based on your description, it's important to note that IONOS and Microsoft 365 are two separate email systems. Simply adding MX records for both providers will not merge or synchronize the mailboxes between them.

The MX record determines which email system receives incoming messages for your domain, so it should generally point to one primary email service to ensure mail delivery remains consistent and predictable.

If your goal is to make Microsoft 365 your primary email platform while keeping your existing email addresses, I'd recommend the following approach:

• Add and verify your domain in Microsoft 365 (Typically, you'll first add a TXT record to verify domain ownership.)
• Create the required user accounts, assign Microsoft 365 licenses that include Exchange Online, and prepare any user or shared mailboxes you need.
• Configure an IMAP migration to copy existing email data from IONOS to Microsoft 365.
• Validate that the email data has been migrated successfully and that users can access their mailboxes in Microsoft 365.
• Once you're ready to move into production, update your DNS settings by removing the old IONOS MX record and replacing it with the Microsoft 365 MX record. At the same time, make sure the required CNAME and SPF records are added or updated as needed.
• Complete a final synchronization before decommissioning the mailboxes currently hosted with IONOS.

You may find the following articles helpful during the process:

• Add a Custom Domain to Microsoft 365 - Microsoft 365 admin | Microsoft Learn
• Migrating Emails from IONOS Mail Accounts to Microsoft 365 - IONOS Help
• Migrate other types of IMAP mailboxes to Microsoft 365 or Office 365 | Microsoft Learn

Note: This link is shared by community members for your convenience. It points to a third-party site that is not managed or verified by Microsoft. We can’t guarantee the quality, safety, or suitability of any content or software found there. Please review carefully and make sure you understand any potential risks before using it.   

Because this type of migration often involves multiple moving parts, you may find it beneficial to work directly with Microsoft Support if you'd like step-by-step guidance throughout the process.

If you're the Microsoft 365 administrator, you can create a support request from the Microsoft 365 Admin Center. On the bottom-right corner of the page, select Help & support.

Tips: You can switch off the Support Assistant as shown in the screenshot, then type a few short characters into the search box and select Get Help. After that, wait for the Contact Support button to appear and click it. At the final step, be sure to clearly describe your request in the description fields so the support engineers can quickly understand your issue and assist you more effectively.    

Once the support ticket has been opened, a Microsoft technical support engineer can work with you directly and, if necessary, arrange a remote session to guide you through the migration process.

I also want to set appropriate expectations that this is a community forum, and I'm a fellow user helping here. Unfortunately, I don't have access to your Microsoft 365 tenant, backend systems, or the internal tools required to provide hands-on assistance with the migration. What I can do is help explain the available options, share relevant documentation, and point you toward the most appropriate next steps and support channels when deeper assistance is needed.

I sincerely appreciate your understanding, and I hope the information above helps you move forward with your migration plan.

If you found this reply helpful and feel that it provides useful information for your situation, please gently take a moment to click "Yes" on my post.

Thank you very much, and I wish you a smooth migration to Microsoft 365!!

Answer 2

Hi @Jessie - Project Manager,

Just to make sure I understand your goal correctly, are you trying to keep your existing email addresses on your company domain and assign them to your new Microsoft 365 user accounts, or are you looking to combine multiple email accounts into a single Microsoft 365 mailbox?

For example, are you hoping that users can continue using their current email addresses after moving to Microsoft 365, or are you trying to migrate existing emails, contacts, and mailbox data into the new Microsoft 365 accounts as well?

Also, could you confirm whether you're the administrator or you're end-user of your Microsoft 365 business tenant?

Please leave a comment below this post with a bit more detail about your current setup and what you're hoping to achieve. The more I understand your requirements, the better I can suggest the most appropriate and effective solution for your scenario.

Looking forward to your response, and I'll be happy to assist further.

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