Adding a Domain to Office 365

Adding a domain to Office 365 is the basis to establishing your companies identity in Office 365’s cloud. This will be the first step to either creating your full on identity and services in the Office 365 or the stepping stone to extending your on premise network into Office 365. If you ever take your Office 365 exams, 70-346 Office 365 Identities, adding and validating domains are covered extensively.

Do you’ve created a tenant…oh vernacular. A tenant in the Office 365 works is really your space. Why they call it a tenant comes from how they use Active Directory in the background. This becomes evidently more clear when you are working with identities. In a hosted environment when you set up the Active Directory, you are not doing it with the idea of a single company, you are now designing it to host many companies and these companies who you are hosting for become your tenants. They get their own Organization Unit, they get their own UPN and they operate like a AD within an AD.

So once you’ve signed up and you have your Office 365 tenant. You will either want to sign up for a domain and add it, or add a pre-existing domain to Office 365. To add a pre-existing domain, on the left menu click on Domains. In the list of domains you will see that you have a default one, this default domain is typically your and it’s just a place holder. If you wish just to test out Office 365, this domain is fully usable, if not kind of ugly. You didn’t come here however to learn how to use their domain, you’ve come here to use your own. To do this Click Add Domain

Add Domain


The next page will be the Add Domain page, which will guide you through adding your domain to Office 365.

Hit the Let’s get started link

Here you will be presented with two options.

1. Add your existing domain or

2. Buy a domain

Which Domain

Click Next

On the next screen you will be prompted to add a DNS record into your DNS provider. The record of preference is a TXT record. This record is harmless to the rest of your DNS, and will simply exist to allow Microsoft to validate that you own this domain. To do this go to your DNS provider or have your partner who is helping you perform this step.

Office 365 TXT record


GoDaddy’s screen



Once, you save it can take up anywhere from 1 hour to 24 hours to populate and read the new DNS record, once DNS has been updated you will be greeted with a message saying.

DNS updatedOnce you click next, you will be prompted to associate your new domain to your users or you can skip this step and proceed to do this later. We will skip these steps and add users later in another post.

in Step 3, you are prompted to finish setting up the domain. I prefer to update my DNS records manually and this will really depend on which Office 365 services you intend to use. If you are using Lync in Office 365 you will need to setup some A, CNAME and SRV records in your DNS provider, if you use exchange you will need mx and cname records and if you are planning to use a Hybrid environment, this DNS setup will be much more complex. Once you ignore all of the DNS records you can go ahead and click Finish

Back in the domains window you will notice that your new domain is now in a “setup complete” Status…good job, you’re ready to go.

domain added



  1. I truly appreciate this article post.Really thank you! Want more. Feddes

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