We have already demonstrated how to add a Domain to Office 365 – Plan P (Fully Redelegated DNS Zone)
In this Screencast, we will demonstrate adding a domain to Office 365, Plan E. While the P Plans are suitable for small companies and come with a lower price, the E plans are designed to cover the needs of companies from 50 to tens of thousands of users and come with much greater flexibility.
As you will see, the process of adding a domain to Office 365 E plan is more complex. On the first place, there is no way to fully redelegate your DNS zone and you need to create the required DNS records manually.
In addition, you have to be careful when specifying Domain services for the domain which you have added.
Your root domain (in our demo – castbuster.com) Fig1 cannot be assigned to SharePoint Online together with any other service – Exchange and Lync online Fig2 . Instead, you need to add a third level domain (e.g., teamsite.castbuster.com) and assign it specifically to your SharePoint Public Website.
As usual, we are following our Step-by-Step approach and at the end we demonstrate the new domain in action: creating a new Global Administrator, configuring Outlook Anywhere and setting a mobile iPad client.