How to setup Microsoft Outlook custom domain for free email hosting?

If you are looking for a custom domain email on a reliable host for free, then Microsoft Outlook is the best free solution. Microsoft Outlook custom domain provides free services for at least 500 users(Update: 50 users by default; need more? Ask Microsoft team with your domain name. They are easily adding more accounts) of your small business or organization. If you want to be email provider then Microsoft Outlook for custom domain is also best choice. You may do this without spending a single penny.