Thanks Bernny for your quick response,
For your information the reason I talked about "Custom Domains" on Windows Live Admin Center was because I was following this tutorial:
www.zdnet.com/why-i-use-outlook-com-for-my-custom-email-accounts-and-how-you-can-too-7000015546
I was trying to add custom emails as described above to avoid having to pay for additional license for each email I added. $6/month is too expensive for each additional email account.
Thank you.....................Murray