Connect your domain to Microsoft 365 (verify and DNS records)

Connect your own domain (for example yourbusiness.co.uk) to Microsoft 365 so your team can use addresses like name@yourbusiness.co.uk instead of the starter onmicrosoft.com address. You'll prove you own the domain, then add the DNS records that send your email to Microsoft 365.

• Applies to: Microsoft 365 Business Basic, Standard and Premium
• Time: about 30 minutes, plus DNS update time
• Difficulty: Intermediate

Before you start

• You'll need a Microsoft 365 Global Administrator sign-in (the admin account Host Dada sent you). See First sign-in to Microsoft 365.
• You'll need access to wherever your domain's DNS is managed. If your domain uses Host Dada nameservers (ns1.kandekore.net to ns4.kandekore.net), that's the Host Dada Control Panel.
• Plan the order. The safe order is: add and verify the domain, create your users and mailboxes, then switch the MX record. Switching MX first means email for anyone without a mailbox will bounce.

Step 1: Add the domain and verify you own it

1. Sign in to the admin centre. Go to admin.microsoft.com and sign in with your admin account.
2. Open Domains. In the left-hand menu select … Show all, then Settings → Domains. (If this is your first domain, you can also start from Setup → Get your custom domain set up.)
3. Select + Add domain. Type your domain name, e.g. yourbusiness.co.uk, and select Use this domain.
4. Choose how to verify. Microsoft may offer to sign in to your DNS provider automatically. Host Dada DNS doesn't use that automatic method (Domain Connect), so if you're offered a choice, pick Add a TXT record to the domain's DNS records and select Continue.
5. Copy the TXT value. Microsoft shows a value like MS=ms12345678. Copy it.
6. Add the TXT record. In your DNS, add a TXT record on the root of the domain with that value. On Host Dada nameservers this is done in Manage DNS; see Microsoft 365 DNS records on Host Dada nameservers for the exact steps.
7. Select Verify. It usually succeeds within 10 to 15 minutes. If it doesn't, wait a while and try again; it can occasionally take longer.

Step 2: Add your users

Once the domain is verified, create a user and mailbox for everyone who receives email at the domain, and add aliases for any extra addresses (for example info@ or sales@). See Add a user and assign a licence, Add an email alias and Create a shared mailbox.

If you already created users with an onmicrosoft.com address, change their username to the new domain under Users → Active users → select the user → Manage username and email.

Step 3: Add the DNS records for email

1. Continue the domain wizard. After verification you'll see How do you want to connect your domain? Select Continue. (If you're shown More options, choose Add your own DNS records, then Continue.)
2. Pick the services. On Add DNS records, make sure Exchange and Exchange Online Protection is ticked. Leave Advanced options alone unless you know you need them.
3. Expand each record type. Select the arrow next to MX Records, CNAME Records and TXT Records to see the exact values.
4. Add them at your DNS provider. In another tab, add the MX, autodiscover CNAME and SPF TXT records, and remove the old provider's MX record. Host Dada DNS customers can follow Microsoft 365 DNS records on Host Dada nameservers.
5. Select Continue. Microsoft checks the records. When it finds them you'll see Domain setup is complete. Select Done.

Step 4: Make it your default domain (optional)

To make new users get your own domain automatically, go to Settings → Domains, select your domain and choose Set as default.

Next steps

• Turn on DKIM and DMARC to help your email avoid junk folders: Turn on DKIM and DMARC for Microsoft 365.
• Set up Outlook on your computers and phones: Outlook for Windows, iPhone and Android.

Troubleshooting

"This domain is already in use" or "already added to another tenant"

A domain can only belong to one Microsoft 365 organisation. If you (or a previous supplier) once set it up in a different tenant, it must be removed from there first. Open a ticket and we'll help you work through it with Microsoft.

Verification keeps failing

Check that the TXT record is on the root of the domain and that you edited the DNS at the provider your nameservers actually point to. If your domain's nameservers aren't Host Dada's, records added in the Host Dada Control Panel won't be seen. See What are nameservers?

The domain shows "Incomplete setup" or "Possible service issues"

Open Settings → Domains → your domain → DNS records. Microsoft lists each expected record with a status, so you can see which one is missing or wrong.

Last reviewed: October 2026