Changing Company Name

To change your company name, domain name, and email address in Microsoft 365, you can follow these steps:

1. Change Your Domain Name: If you want to change to a new domain name, you will need to add the new domain to your Microsoft 365 account. You can do this by going to the Microsoft 365 admin center, navigating to Settings > Domains, and selecting Add domain. Follow the prompts to verify ownership of the new domain.
2. Change Email Address: After adding the new domain, you can change the email addresses of your users. Go to Users > Active users, select the user whose email you want to change, and edit their username to reflect the new domain.
3. Email Forwarding: To forward emails from the old email address to the new one, you can set up a forwarding rule in Outlook. This can be done by going to the Settings in Outlook, selecting Mail, and then Forwarding. You can enter the new email address where you want the emails to be forwarded.
4. Sign Out and Sign Back In: After making these changes, ensure that you sign out of Microsoft 365 and then sign back in with the new email address to complete the process.

Make sure to notify your contacts about the change in your email address to avoid any confusion.

References:

• Change your Microsoft 365 email address to use your custom domain
• Change a user's email address

Hi @Melanie Nigrinis, 

Thank you for posting your question in the Microsoft Q&A forum.  

Based on your description, you are changing your company name and want to update your Microsoft 365 domain and Outlook email address while ensuring email continues to arrive at the new address. We truly understand this transition takes thoughtful preparation and appreciate the effort you are investing. 

When a company name or domain changes, Outlook and Microsoft 365 treat this as a domain update within your organization. Your new domain must first be added and verified in Microsoft 365 before you can assign the new email addresses. After this configuration, your existing mailbox and emails remain intact, nothing will be lost during the process. You can also set up forwarding so messages sent to your old address are automatically delivered to your new one.  

Below are some workarounds that suit for your situation: 

1/ Start by registering the new domain and confirming its validity (admin only). 

• In Microsoft 365 admin center, go to Setup then Domains, choose Add domain, and complete TXT DNS verification. Wait for DNS propagation.  

• Once verified, go to Users > Active users, select each user, and update their Username/Email to use the new domain.  

2/ Proceed by updating address details and confirming mail flow functionality. 

• Set the new domain as default, change your sign in UPN and primary SMTP to the new domain, and keep the old address as an alias or configure forwarding.  
• Update MX, SPF, and Autodiscover records to the tenant values. Set up SPF identify valid email sources for your Microsoft 365 domain - Microsoft Defender for Offi… 

3/ Next, ensure classic Outlook is refreshed and synchronized on every device. 

• Restart Outlook to pick up the change. If it still prompts for the old address, create a new profile from Control Panel then Mail then Show Profiles then Add, and sign in with the new address.  
• To forward old emails, open Outlook (Classic), go to File > Manage Rules & Alerts, and create a new rule to forward emails from your old address to your new one. 

4/ After that, execute comprehensive testing and confirm end-to-end results. 

• Send test messages to both the old and new addresses, verify delivery, and confirm calendar and shared access after directory and DNS updates finish syncing. 

5/ As your account is managed by your organization, please contact your IT administrator to check your permission, policies, and help you add new domain. 

As community moderators, we appreciate your understanding that our access to internal development details is limited. Our primary role is to guide users toward the appropriate resources and support channels. While we may not have visibility into deeper backend analysis, we’ll continue doing our best to support you within the scope of our responsibilities.  

I hope this information is helpful. Please follow these steps and let me know if it works for you. If you have any updates regarding the issue, please feel free to share them with me.   

Thank you for your patience and your understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.   

I look forward to continuing the conversation.  

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