Domains FAQ

This article contains answers to Frequently Asked Questions about domains in Office 365.

If you can't find an answer to your question, let us know by leaving a comment and we'll add it to the list.

Last Updated: 3/22/17

• What is MX priority?

• How can I validate SPF records for my domain?

• How does Office 365 manage my DNS records?

• What is a domain name?

• Can I transfer my domain away from Office 365 to another provider?

• How do I change how my DNS records are managed in Office 365?

• What happens if my DNS provider doesn't support certain record types?

• How do I change the default domain in Office 365?

• Can I add custom subdomains or multiple domains to Office 365?

• Why do I have an "onmicrosoft.com" domain?

What is MX priority?

Mail is delivered to the mail exchange server with the lowest preference number (highest priority), so the MX record you use for mail routing should have the lowest preference number, typically 0 or High priority.

• When you create an MX record, most DNS hosting providers require you to set the preference number.

• Some label the box preference, and some label it priority.

• Some require a number, and some ask you to select Low, Medium, or High.

• If you only have one MX record, any value is fine for priority or preference.

• If you have more than one, make sure the MX record for mail routing is higher priority than the one used for validating that you own the domain.

How can I validate SPF records for my domain?

It's important that you have or create only one TXT record for SPF. If you already have an SPF record, you should append the new Office 365 values to it, rather than create a new one. After you've added or updated your SPF record for Office 365 email, you should check to make sure that the syntax is correct with one of these tools:

• SPF Record Testing Tools 

• SPF Surveyor 

• Dig web interface 

How does Office 365 manage my DNS records?

There are two options for DNS management with Office 365:

1. You change your nameserver (NS) records, and then Office 365 takes care of all the service-specific records, like setting up your MX record for email. (Recommended)

2. You add DNS records for email and other Office 365 services at your DNS host yourself. (Experts only)

1:  Office 365 creates and hosts the DNS records

2: You manage the DNS records yourself

Advantages You don't have to worry about making mistakes in the values you enter for the DNS records for Office 365 services. You have more flexibility in your choice of domain registrar and DNS host. Any provider that lets you change your nameserver records will work, even if the provider doesn't support all the required record types. When Office 365 adds new DNS records, you don't have to make updates. Disadvantages You can't change your DNS records to host email outside of Office 365. If you already use a public website with your domain for its address, like www.fourthcoffee.com, you must redirect people to that address from Office 365. Setting up redirection requires a static IP address, which is not always easily available for public websites. If your current domain registrar doesn't allow you to change your domain's nameserver records, you have to switch to a different registrar to use this DNS management option.

Advantages You control the DNS records for Office 365 services. If you have a public website with your domain for its address, like www.fourthcoffee.com, you don't have to worry about using redirection to make sure people can still get to your website after you set up your domain in Office 365. You have the flexibility to host email somewhere else, such as with an on-premises Exchange server. Disadvantages You have to set up the DNS records for Office 365 services yourself (unless you have a GoDaddy domain). If your current DNS host doesn't support all of the required record types for Office 365, some Office 365 features won't be available and you might need to switch to a different DNS host. Learn about the potential service limitations. When Office 365 changes requirements for DNS records, or adds new services, you have to make updates yourself at your DNS host.

What is a domain name?

A domain is a unique name that appears after the @ sign in email addresses, and after www. in web addresses. It typically takes the form of your organization's name and a standard Internet suffix, such as yourbusiness.com or stateuniversity.edu.

Using a custom domain like "rob@contoso.com" with Office 365 can help build credibility and recognition for your brand.

You can buy a domain in Office 365 and we'll set it up automatically, or you can buy or bring one you already own from a domain registrar.

Can I transfer my domain away from Office 365 to another provider?

Yes - there are two limitations to be aware of:

• You can't transfer a domain to or from Office 365 unless you registered the domain at Office 365.

• You can't transfer an Office 365 domain to another registrar until 60 days after you registered it with Office 365.

Follow the steps below to get the code at Office 365, and then go to the other domain registrar's website to set up transferring your domain name to that registrar.

1. Choose Domains after you log in to the Office 365 admin center.

2. Select the Office 365 domain that you want to transfer to another domain registrar, and choose Domain settings.

3. Under Privacy Setting, choose Enable domain transfer.

4. Follow the steps to prepare for transferring your domain.

5. After you get the code, go to the website of the domain registrar where you want to manage your domain name going forward and follow their directions for transferring a domain (search for help on their website).

6. If you need to see the code again, on the Domain settings page in Office 365, choose View authorization code for domain transfer.

After the transfer is complete, you'll renew your domain at the new domain registrar and manage your domain's nameservers there.

How do I change how my DNS records are managed in Office 365?

Change DNS management to a DNS host outside Office 365

1. Change your nameservers

   1. Sign in to the domain registrar for your domain. 

   2. Find the area on the registrar's website where you update nameserver records, and update the nameservers to point to your domain's DNS host. (The DNS host is often the domain registrar.)

2. Follow a link to go to the domains setup wizard

   1. Sign in to Office 365 and go to the admin center

   2. Go to the Domains page

   3. Select the domain you're switching, and choose DNS Management.

3. Choose the option to manage your domain's DNS records

   1. In the domains setup wizard, on the Set up your online services page, choose I'll manage my own DNS records, and then click Next.

   2. Add the DNS records suggested by the wizard on the Update DNS settings page to your registrars website. 

   3. After you've added the records, come back to Office 365 and click Verify.

Change DNS management to Office 365

1. Follow a link to go to the domains setup wizard

   1. Sign in to Office 365 and go to the admin center

   2. Go to the Domains page

   3. Select the domain you're switching, and choose DNS Management.

2. Choose the option to manage your domain's DNS records

   1. In the domains setup wizard, on the Set up your online services page, choose Set up my online services for me. (Recommended), and then click Next.

   2. If you haven't verified the domain yet, follow the steps to do that first.

   3. On the Update DNS settings page, we list the nameservers for Office 365. Go to the domain registrar for your domain, and update the nameservers to the Office 365 nameservers.

   4. After you've updated the nameservers, wait at least an hour. Then, back in the wizard in Office 365, click Verify.

What happens if my DNS provider doesn't support certain record types?

If you manage your own DNS records and your DNS host does not support all the DNS records that Office 365 needs, some Office 365 features won't work. We recommend that you transfer your domain to a registrar that supports all required DNS records.

Providers that support all required DNS records:

• Dynadot

• eNomCentral

• Europe Registry

• GoDaddy

• Hover

• MyHosting.com

• Name.com

• Nearly Free Speech

• Nettica

• Network Information Center (NIC)

• Network Solutions

• Register.com

If SRV records are not supported, the following Office 365 features are not available:

• Skype for Business Online IM and presence integration with Outlook Web App

• External communication (federation) with Skype for Business Online users in other organizations.

• Public Internet Connectivity (PIC) with Skype for Business Online users signed in with a Microsoft account (formerly known as a Windows Live ID).

If multiple CNAME records are not supported, you have to choose between the following features for Skype for Business Online:

• Email desktop clients and mobile clients can use Autodiscover to automatically find the Exchange Online service so that users can sign in without having to enter a server name.

• Skype for Business Online desktop clients can use Autodiscover to automatically find the Skype for Business Online service so that users can sign in without having to enter a server name.

• Skype for Business Online mobile clients can use Autodiscover to automatically find the Skype for Business Online service so that users can sign in without having to enter a server name.

If SPF/TXT records are not supported, other people may be able to use your domain to send spam or other malicious email. SPF records work by identifying the servers that are authorized to send email from your domain.

How do I change the default domain in Office 365?

You must have at least one custom domain that you've added to Office 365 before you can choose a default domain.

1. Sign in to Office 365

2. Open the Domains page

3. On the Domains page, choose the domain you want to set as the default for new email addresses.

4. Click Set as default.

You cannot change the name of your initial .onmicrosoft.com domain.

Can I add custom subdomains or multiple domains to Office 365?

Yes. Typically, you can add up to 900 domains to your Office 365 subscription.

For example, you could add the domains contoso.com and contosomarketing.com, and then add the subdomains www.contoso.com, www.partners.contoso.com, www.partners.marketing.contoso.com, and so on.

When you add multiple domains to Office 365, you can host any of the services (like email) on any of the domains you've added. When you change your email to Office 365, by updating a domain's MX record, ALL email sent to that domain will start coming to Office 365. 

Why do I have an "onmicrosoft.com" domain?

Office 365 creates a domain for you, like contoso.onmicrosoft.com, when you sign up with the service. The user ID that you create when you sign up includes the domain, like alan@contoso.onmicrosoft.com.

If you want to have your email look like alan@contoso.com: buy the domain or just follow the steps in Add your users and domain to Office 365 if you own it already.

• You can't rename the onmicrosoft domain after sign-up. For example, if the initial domain you chose was fourthcoffee.onmicrosoft.com, you can't change it to be fabrikam.onmicrosoft.com. To use a different onmicrosoft.com domain, you'd have to start a new subscription with Office 365.

• You can't rename your team site URL. Your team site URL is based on your onmicrosoft.com domain name, and because of the way SharePoint Online architecture works, unfortunately you can't rename the team site.

• You can't remove your onmicrosoft domain. Office 365 needs to keep it around because it's used behind the scenes for your subscription. But you don't have to use the domain yourself after you've added a custom domain.

You can keep using the initial onmicrosoft.com domain even after you add your domain. It still works for email and other services, so it's your choice.