I am using outlook.com for my own email "mydomain.info" but I can not add an account in Apple Mail. I have searched in Ask Different for similar questions. I got this: Personal domain email using Outlook.com on Apple Mail
I have exact the same problem but the accepted answer doesn't work for me. My domain is "domain.info". I never configured an account successfully in Apple Mail from Maverick to Yosemite and now El Capitan.