Add a domain to Microsoft 365 (verify only)

Your company might need multiple domain names for different purposes. For example, you might want to add a different spelling of your company name because customers are already using it and their communications failed to reach you.

At the end of these steps, your domain stays registered with the host that you purchased the domain from, but Microsoft 365 can use it for your email addresses (like user@ycontoso.com) and other services.

If you don't add a domain, people in your organization use the onmicrosoft.com domain for their email addresses until you do. It's important to add your domain before you add users, so you don't have to set them up twice.
Let's start add a domain to Microsoft 365 tenant.

Preparation.

• Your domain name wants to verify example: itso.work365.site.
• Account manages public DNS or contact support.
• Microsoft 365 account with Global Administrator account

Step 0: Scope of article.

This article provide step add a domain to Microsoft 365 only, not verify another service.

Step 1: Add a domain to Microsoft365.

Go to Microsoft 365 admin center > Settings > Domains > click Add domain.

Enter domain name "itso.work365.site and click Use this domain.

Select Add a TXT record to the domain's DNS record and click Continue.

Copy TXT value keep value to create DNS record or send to support domain and then click verify (for check the domain not verify another tenant).

After verify show error does not detect DNS record for this domain and click cancel.

It back to Domains page and show the domain name itso.work365.site and status "Incomplete setup"

Step 2: Create public DNS record for verify domain name.

This example DNS record you must send information to support public DNS
Example: If you verify with sub domain (use in article).

Example: If you verify with primary domain.

This step for you can manage public DNS.

Login you public DNS manager and create TXT record follow image.

After you created DNS record, you can check public DNS with MXToolbox for testing DNS record have update?

Go to https://mxtoolbox.com/ lookup with TXT Lookup and show detect DNS record follow image.

Step 3: Completed add a domain.

Go back to Settings > Domains > select the domain "itso.work365.site" and click Start setup.

Click Continue.

Click Verify again.

Click Continue.

Uncheck "Exchange and Exchange Online Protection.

The Domain setup is complete and then click Done.

On Domains page show domain name itso.work365.site and status are no services selected.

Step 4: Test domain is work.

Go to Active Users and click Add a user, and enter information and define domain name "itso.work365.site"

Select create user without product license.

Click Next (default Roles: User no administrator access).

Finish adding.

Show password and then keep username and password.

After Close the user show account and licenses.

Go to https://login.microsoftonline.com and enter credentials.

That account can sign-in, but not any license assign to this user.