How To Add A New Public Domain To Office 365

When we sign up for Office 365, initially we get a default domain in the format XXXX.onmicrosoft.com. In order to spin up to a trial version and do some testing of the environment, this domain is perfectly okay. However, if we want to deploy the Office 365 service to an organization, we will have to get a custom domain so that the customers and users can identify the organization by the URL. 

The scope of the article would cover the following main points.

• Add a domain
• Verify the domain
• Update the DNS Settings
• Set primary domain

Add a Domain

We have two options when it comes to adding a new domain to Office 365.

• Buy a new domain from Office 365 Admin Center
• Use an existing owned domain and add it to the Office 365

Let's see how we can achieve both.

Buy a new domain from Admin Center

Office 365 Admin Center provides the global administrator an option to buy a new domain from Settings -> Domains section.

Here, click on the “Buy domain” button to navigate to the page where we can buy a new domain from.



It will take us to the page where we can search for a suitable and available domain name.

Once we have found a suitable match, click on "Buy" which will take us to the GoDaddy site to complete the purchase.



Click on "Go to GoDaddy.com".



The total amount and the duration of ownership can be specified into the GoDaddy site.



Once the payment is completed, a dialog box will appear which requests for permissions so that the Office 365 can make domain entries in the GoDaddy domain center. Click on "Accept".



This will take some time.



Once it is completed, head over to the Office 365 Domains page and we can see the new domain listed out.



Add an existing domain to Office 365

However, there can be instances where we already own a domain and we have to use it with Office 365. In such a scenario, go to the domains page and click on Add domain.



Specify the name of the domain that you own in the text box, as shown below.



Verify Domain

Office 365 will now want to verify that you really own such a domain. You can choose ‘Sign in to GoDaddy’ so that it automatically contacts the domain registrar to do verification.



In order to automate the verification, a GoDaddy login screen will come up where you have to authenticate to GoDaddy by entering the username and password.



Allow Office 365 to make changes to the domain at GoDaddy by clicking on "Accept", and this will automatically verify the domain.



If you have successfully verified the domain, go to the next step “Update DNS Settings”. However, there may be cases where we have to do it manually, in case the OAuth login to GoDaddy fails. In such a case, we will have to add the TXT record provided by Office 365 to GoDaddy (or any other domain registrar you have chosen).



After clicking "Next", we will be provided with TXT record values which we will have to add to the GoDaddy site.



Log into your Domain Registrar site. In my case, it is GoDaddy. Select "Manage DNS".



It will, by default, have some domain records required for the functioning of the domain. Click on "Add" to create a new TXT record for domain verification.



From the dropdown, select ‘TXT’.



Add the values provided by Office 365 in the below text boxes. Host corresponds to the TXT Name provided by Office 365.



Once you have added it, it comes up in the records.



Head back to Office 365 and click on ‘Verify’ button in the page. If the entry added in the domain registrar page is correct, we will get the below success message.

Update the DNS Settings.

Once we have verified the domain, we have to update the DNS Settings. Similar to the above step, we can automate this step by selecting the first option ‘Add the DNS records for me’.

Authenticate to your domain registrar by adding the user name and password and the domain setting will be automatically update to the domain registrar by Office 365.

If this step completes successfully, head to the next step “Set Primary Domain”. In case of any authentication failure, we will have to update the DNS records manually. Select “I’ll add the DNS records by myself” and click on "Next".

This will fetch a set of DNS records that we will have to update manually at the domain registrar’s site.

 

 

 The set of records that we will have to update are -

• MX Records
• CNAME Records
• TXT Record
• SRV Records

Add MX Records

First, let’s add the MX record which will redirect the mails so that all the mails coming to the domain will be redirected to Office 365 mailbox. We will have to add 1 MX record provided by Office 365 at the domain registrar site. Office 365 has also listed out 2 records which are already present in the domain registrar site (mailstore.secureserver.net and smtp.sercureserver.net) which we will have to remove from the domain registrar.



Select the edit icon and click on the Trash Bin icon against both the pre-existing MX records.



Now, click on the "Add" button and select MX from the drop down.



Specify the values provided by Office 365 and click on Save.



This will add the new MX record provided by Office 365.



Clicking on "Verify" button in the Office 365 page will check for the validity of the newly added MX record, as shown below.



Add CNAME Records

Now, let’s add the CNAME records. CNAME stands for Canonical Name. We have 6 missing entries which will have to be created at the domain registrar.



The first 4 are required for various services like Outlook and lync. The last 2 CNAME records starting with enterprise are required for Mobile Device Management.

Click on "Add" and select CNAME from the dropdown.



Specify the values provided by Office 365 and click on Save.



Do this for all the 6 record entries provided by Office 365.



Head back to Office 365 Admin Center and click on "Verify". It will display a tick mark against the missing CNAME records indicating successful updation.



Add TXT Record

Now, we have to add the TXT record. This TXT record is added for prevent spoofing.



Head over to domain registrar and add the TXT record with the values provided by Office 365.



Verify the newly added TXT record in the Office 365 Admin Center.



Add SRV Record

Finally, add the SRV record. SRV (Service Records) is a specification of the hostname and port number of the servers providing the services.

As shown below, we have to add 2 SRV records.



Select SRV from the dropdown in the "Domain Records Management" page of the domain registrar.



Add the values as provided by Office 365 and click on Save.



This will list out all the added domain records in the domain registrar’s page.



Make a final verification by clicking on "Verify" button in the Office 365 page and we should get the below success message which states that the domain and email addresses are set up.



Set Primary Domain

Heading over to the Domains page in Office 365, we can see that the new domain has been added and successfully set up.



Click on the new domain and set it as default if you want to start using it.



Thus, the newly added domain has been set as the default domain in Office 365.



As a final step, we have to go to the list of users and edit their emails to start using the new domain.



Click on "Edit" option against the user name.



Add the new domain email address, select "Set as primary", and click on Save.



We will, thus, get an onscreen message about the change in email address.



Summary

Thus, we saw how to add a new domain in Office 365 and start using the new domain for email relay in Office 365.